Answer:
The wind energy and solar energy have their own benefits when producing electricity but one of their major drawbacks is that both these energy form depends on the environmental conditions and cannot be stored.
On the other hand, in hydroelectric pumped storage, water is stored in the form of gravitational potential energy. If not enough water is there to produce electricity, then this stored water can be run over turbines to produce electricity. Hence, this is one benefit of hydroelectric pumped storage over wind and solar energy.
Answer:
These pumps allow the energy to be saved for future use, whenever the load increases.
Explanation:
Pumped-storage hydropower (PSH) is a type of hydroelectric energy storage. It is a configuration of two water reservoirs at different elevations that can generate power (discharge) as water moves down through a turbine; this draws power as it pumps water (recharge) to the upper reservoir.
PSH capabilities can be characterized as open-loop—where there is an ongoing hydrologic connection to a natural body of water—or closed-loop, where the reservoirs are not connected to an outside body of water.
2- A gas has a volume of 500 mL at a temperature of -73.0 °C. What volume will the gas
occupy at 27.0°C?
Answer: 750ml
Explanation:
Using charle's law
V1/T1=V2/T2
V1= 500ml
T1= -73⁰C
V2= ?
T2=27⁰C
We can see that the temperature is in Celsius
Now,we will convert to Kelvin
Kelvin= 273+ Celsius
So convert the Celsius value to Kelvin
For T1= 273+(-73)
T1= 273-73
T1= 200K
For T2= 273+27
T2= 300K
V1/T1=V2/T2
500/200=V2/300
Cross multiply
200×V2=500×300
200V2= 150000
V2= 150000/200
V2= 750ml
So,
750ml of gas will occupy at 27⁰C
Answer:
750mL
Explanation:
Charles law states that the volume of a fixed mass of gas is inversely proportional to its temperature, at constant pressure
Mathematically,
V1/T1 = V2/T2
Values given are;
V1=initial volume of the gas=500mL
T1=initial temperature of the gas=-73.0°C=(-73.0+273)K=200K
V2=final volume of gas
T2=final temperature of gas=27.0°C=(27.0+273)K=300K
The volume of the gas at 27°C is unknown.
We'll make V2 subject of the formula
V1/T1=V2/T2
V2=(V1×T2)/T1
V2=(500×300)/200
V2=750mL
Therefore, the gas will occupy a volume of 750mL at 27.0°C
If a reaction occurs, what will be the products of the unbalanced reaction
below?
Mg(s) + H2O(1) ►
The Activity Series of Elements
O A. MgO(s) + H2(9)
O B. Mg(OH)2(aq) + H2(g)
O c. MgHz(s) + O2(9)
O D. No reaction will occur.
The products of the unbalanced reaction is Mg(s) + H₂O → Mg(OH)₂(aq) + H₂(g)
What is balanced equation?An equation for a chemical reaction is said to be balanced if both the reactants and the products have the same number of atoms and total charge for each component of the reaction. In other words, both sides of the reaction have an equal balance of mass and charge.
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4. Calculate the final concentration if water is added to 1.5 L of a 12 M
NaOH solution to make 3.0 L of a diluted NaOH solution.
Your answer
Answer:
6M
Explanation:
(Molarity x Volume)concentrated soln = (Molarity x Volume)diluted doln
Molarity dilute soln = [(M x V)conc/V (dilute)] = 1.5L x 12M / 3.0L = 6M final dilute soln
Which are caused by global warming?
a. Extreme weather conditions
b. Displaced animal habitats
C. Sea level rising
d. All of the above
If I mixed milk and vinegar together would it be a chemical or physical change?
Answer:
A chemical change
Explanation:
Which sweet tea would you expect to taste the sweetest?
Here is the clear picture
Answer: You're right, it's 8 M
Explanation: The higher the number, the sweater it is.
As the concentration of sugar solute molecules increases, the more sweeter the solution will be. Here, 8 M sugar solution is the sweetest one.
What is molarity?
Molarity of a solution is a term use to represent its concentration. It is the ratio of number of moles of solute to the volume of solution in litres. Molarity is a temperature dependant property.
Higher the number of moles of the solute higher is the molarity. When it made more diluted by adding more volume its concentration decreases thereby molarity.
8 M sugar solution contains 8 moles of sugar molecules per one liter of water. Which is higher in concentration than the other given concentrations and thus having more sweet.
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How many grams of CO2 are produced from 51 g of CH4?
Answer:
140.25g of CO2
Explanation:
First, let us write a balanced equation showing how CO2 is produced from CH4. This is illustrated below:
When CH4 undergoes combustion it produces CO2 and H2O according to the balanced equation below:
CH4 + 2O2 —> CO2 + 2H2O
Next, let us calculate the mass of the CH4 that reacted and the mass of CO2 produced from the balanced equation. This is shown below:
Molar Mass of CH4 = 12 + (4x1) = 12 + 4 = 16g/mol
Molar Mass of CO2 = 12 + (2x16) = 12 + 32 = 44g/mol
From the balanced equation above,
16g of CH4 produced 44g of CO2.
Therefore, 51g of CH4 will produce = (51 x 44)/16 = 140.25g of CO2.
From the calculations made above, we can see that 51g of CH4 produced 140.25g of CO2
Answer:
139.91 g CO2 to the nearest hundredth.
Explanation:
CH4 + 2O2 ----> CO2 + 2H2O
Using the molar masses of the chemicals:
(12.011 + 4*1.008) g CH4 produces (12,011 + 32) g CO2
So 51 g of CH4 produces [51 * (12,011 + 32] / [ (12.011 + 4*1.008) ]
= 139.91 g CO2.
In a modern system of classification, two organisms would be
most closely related if they were classified in the same
A
kingdom
C
genus
8
phylum
0
species
Answer:
could be species I think
Within the taxonomy, organisms are organized hierarchically, the biological species is the set or natural population of organisms that are recognized because they are similar in form and function.
What is a biological species?It is a set of organisms capable of reproducing and obtaining fertile (non-hybrid) offspring, and that share their basic defining evolutionary traits.
The organisms of the same species share generic characters and other factors that allow them to resemble each other and distinguish themselves from the rest of the species.
Therefore, we can conclude that many species share evolutionary origins or are evolutionarily related from some common ancestor.
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Which label best classifies all three of these steps?
A chemical reaction takes place.
Reactants are gathered in chloroplasts.
Energy is used to make food.
Oxygen is produced and stored in the plant.
Answer:
a
Explanation:
a
Answer:
Reactants are gathered in chloroplasts.
Explanation:
Photosynthesis is a process unique to autotrophic organisms like plants. It is the process whereby plants use energy from sunlight to make their own food (chemical substance). The photosynthetic process occurs in two stages in the Chloroplast viz: Light dependent stage and light-independent stage.
In the light dependent stage, the plant captures energy from sunlight via its Chlorophyll pigment and uses it to break down water molecules (H2O) in a process called PHOTOLYSIS OF WATER. This process brings about the electrons and protons needed to form NADPH and ATP molecules respectively. This process occurs in the thylakoid membrane of the CHLOROPLAST.
In the light independent stage, also known as Calvin cycle, the plant uses the NADPH and ATP molecules produced in the light stage to reduce Carbondioxide (CO2), which enters through the stomata of the plant, and power the formation of glucose molecule (C6H12O6).
Hence, based on the steps listed by Jeremy for the photosynthetic process, the gathering of reactants (CO2, H2O and light energy) in the Chloroplast of the plant best classifies those steps
what property of elements causes waters polarity
Answer:
atoms bond mixes with oxygen
Explanation:
Just search it up on google dum dum
The most highly concentrated hydrochloric acid is 12 M. What volume of a 12 M stock solution of HCL should be diluted in order to produce 6.0 L of 0.50 M HCL?
A. 1.0 L
B. 3.0 L
C. 250 mL
D. 500 mL
The volume of that 12M stock solution of HCL must be diluted to generate 6.0 L of 0.50 M would be:
C). 250 mL
Find the volumeGiven that,
Stock solution of HCL = 12 M
Amount of HCL to be produced = 6.0 L of 0.50 M
To find,
The volume of stock solution = (0.5 × 6)/12
= 0.25 l
By converting 0.25 liters into ml,
= 0.25 × 1000
= 250 ml
∵ 250 ml is the amount of HCL required.
Thus, option C is the correct answer.
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What definition BEST describes a watershed?
Select one:
Area that collects precipitation and drains it to the lowest point
Consists only of rivers, lakes, and streams
Place where all water is stored underground
All of the rain water of a specific area
The best definition of a watershed is Option(A) Area that collects precipitation and drains it to the lowest point.
What is a watershed ?A watershed is the area of land where all of the water that drains off at its lowest point of it goes into the same place- a river, stream or lake. The smallest watersheds are the drainage areas for small streams and lakes. It can also be at the lowest point like a creek or a river.
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9)
I have an unknown volume of gas held at a temperature of
115 Kin á container with a pressure of 60 atm. If by
increasing the temperature to 225 K and decreasing the
pressure to 30 atm causes the volume of the gas to be 29
liters, how many liters of gas did I start with?
The initial volume of the gas can be determined using the ideal gas law. The simplified formula was rearranged to solve for the initial volume. The calculation showed that the initial volume was 18.19 liters.
Explanation:The subject of the question can be tackled with the application of the ideal gas law represented by the equation PV=nRT, where P is the pressure, V is the volume, n is the number of moles, R is the gas constant and T is the temperature. However, since the number of moles doesn't change in the problem, we can omit n and R from it and use the simplified version of it, that is P1V1/T1=P2V2/T2. Here P1, V1 and T1 refer to the initial pressure, volume and temperature and P2, V2 and T2 refer to the final pressure, volume and temperature respectively.
To get the initial volume of the gas V1, we rearrange the simplified ideal gas law to V1 = (P2V2T1)/(P1T2). Plugging the given values in the formula we get V1 = (30 atm * 29 L * 115 K) / (60 atm * 225 K) = 18.19 liters.
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The correct answer is that the initial volume of the gas was [tex]14.5 \ liters[/tex].
To solve this problem, we can use the combined gas law, which states that for a given amount of gas, the product of pressure and volume divided by the temperature is constant:
[tex]\[\frac{P_1V_1}{T_1} = \frac{P_2V_2}{T_2}\][/tex]
where [tex]\(P_1\), \(V_1\)[/tex], and [tex]\(T_1\)[/tex] are the initial pressure, volume, and temperature, respectively, and [tex]\(P_2\), \(V_2\)[/tex], and [tex]\(T_2\)[/tex] are the final pressure, volume, and temperature, respectively.
Given:
[tex]\(P_1 = 60\) atm[/tex] (initial pressure)
[tex]\(P_2 = 30\)[/tex] [tex]\(T_1 = 115\) K[/tex] (initial temperature)
[tex]\(P_2 = 30\)[/tex] atm (final pressure)
[tex]\(V_2 = 29\) liters[/tex] (final temperature)
[tex]\(V_2 = 29\) liters[/tex] (final volume)
We want to find [tex]\(V_1\)[/tex] (initial volume). Rearranging the combined gas law to solve for [tex]\(V_1\)[/tex], we get:
[tex]\[V_1 = \frac{P_2V_2T_1}{P_1T_2}\][/tex]
Plugging in the given values:
[tex]\[V_1 = \frac{(30\text{ atm})(29\text{ liters})(115\text{ K})}{(60\text{ atm})(225\text{ K})}\][/tex]
[tex]\[V_1 = \frac{30 \times 29 \times 115}{60 \times 225}\][/tex]
[tex]\[V_1 = \frac{99350}{13500}\][/tex]
[tex]\[V_1 = 14.5\text{ liters}\][/tex]
How does matter move and change through photosynthesis??
Final answer:
Photosynthesis transforms carbon dioxide and water into glucose and oxygen using sunlight energy. This process adheres to the law of conservation of mass, reflecting the transformation of matter without any loss. The resulting carbohydrates are moved within the plant through the phloem, driven by osmotic forces.
Explanation:
How Matter Moves and Changes Through Photosynthesis
Photosynthesis is the biological process that allows plants to convert light energy into chemical energy. During this process, matter in the form of carbon dioxide and water is transformed into glucose and oxygen. Energy from sunlight energizes electrons which, in turn, facilitate the production of energy-carrying molecules like NADPH and ATP during the 'light cycle'. This energy is then used in the Calvin Cycle, or 'dark cycle', to fix carbon dioxide from the atmosphere into glucose, a process that is vital for the cycling of matter and flow of energy through ecosystems.
The law of conservation of mass dictates that the amount of matter remains constant in this process. So, the uptake of carbon dioxide and water and the release of oxygen and glucose reflect a transformation, not a loss of matter. These biochemical processes of photosynthesis support life on Earth, as they produce the basic nutrients that form the foundation of the food chain and release oxygen that is essential for the respiration of most living organisms.
Carbohydrates like sucrose, synthesized during photosynthesis, are then transported from the sites of production to where they are needed within the plant through the phloem. This movement is driven by osmotic forces that arise due to variations in solute concentrations, thus showing how matter moves within the plant system.
The atomic radius of a silver atom is 1.44 x 10-10. Give the
atomic radius of silver in nanometres.
Answer:
0.144 nm
Explanation:
Silver's electronic configuration is (Kr)(4d)10(5s)1, and it has an atomic radius of 0.144 nm.
Can a chemical reaction happen with only one substance? For example, if you select water as the first substance but you don't add another substance, will a chemical reaction happen or not?
Explanation:
Yes, a chemical reaction can happen with only one substance.
A typical example of such reaction is the radioactive decay.
Radioactive decay is the loss of elementary particles from an unstable nucleus, ultimately changing the unstable element into another more stable element. .
When radioactive elements are let alone, they decompose to form stable harmless elements.
An example of radioactive decay is attached in the image below;
Answer:
No
Explanation:
A chemical reaction cannot happen with water alone. This is because, a chemical reaction must involve collision of particles from different reactants in order to give a product. No chemical specie can react with itself without some kind of interaction with another chemical specie which may or may not enter into the rate equation for that reaction.
Only nuclear reactions are spontaneous and involve only one reactant for spontaneous radioactive decay.
Which parameter is measured directly in a coffee-cup calorimeter?
pressure
heat of fusion
temperature
kinetic energy
(c) Temperature
Temperature is measured directly in a coffee-cup calorimeter.
See Attached Image. Figure shows Coffee-cup calorimeter. This simple apparatus is used to measure temperature changes of reactions at constant pressure.
(c) Temperature is measured directly in a coffee-cup calorimeter.
A coffee cup calorimeter:It is essentially a polystyrene (Styrofoam) cup with a lid. The cup is partially filled with a known volume of water and a thermometer is inserted through the lid of the cup so that its bulb is below the water surface.
Out of the given options,
Temperature is measured directly in a coffee-cup calorimeter.
Thus, option C is correct.
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3. Is the number of total molecules on the left side of a balanced equation always equal to the
number of total molecules on the right side of the equation? Explain your answer.
The number of total molecules on both sides of a balanced equation may differ. It is the number of each type of atom that must be equal, not the molecule count, to comply with the law of conservation of matter.
Explanation:The number of total molecules on the left side of a balanced equation does not necessarily have to equal the number of total molecules on the right side. What must be equal are the numbers of each type of atom because chemical reactions follow the law of conservation of matter, meaning that matter is not created or destroyed in a chemical reaction. The balancing of equations ensures that there is the same number of each kind of atom on both sides of the equation, thereby obeying this fundamental law.
However, the actual molecule numbers can vary, as it's the ratio of molecules that must reflect the coefficients in the balanced equation. For instance, if we have 2 H2O (2 molecules of water) as reactants, this could lead to 2 H2 and 1 O2 (3 molecules in total) as products, with 4 hydrogen atoms and 2 oxygen atoms balanced on both sides.
How much heat (in Joules) is needed to raise the temperature of 257g of ethanol (cethanol=2.4 J/g°C) by 49.1°C?
Answer:
30284.88J
Explanation:
Given parameters:
Mass of ethanol = 257g
Specific heat capacity of ethanol = 2.4J/g°C
Temperature change = 49.1°C
Unknown:
Amount of heat = ?
Solution:
The quantity of heat need to cause a temperature change on a body is given as;
H = m c Δt
where m is the mass
c is the specific heat capacity
Δt is the change in temperature
All units in proper dimensions. Input the parameters and solve for H;
H = 257 x 2.4 x 49.1
H = 30284.88J
how many hydrogen atoms are in 35.0 g of hydrogen gas
There are approximately [tex]\(1.045 \times 10^{25}\)[/tex] hydrogen atoms in 35.0 g of hydrogen gas, calculated using its molar mass and Avogadro's number.
To find the number of hydrogen atoms in 35.0 g of hydrogen gas, we need to use the concept of molar mass and Avogadro's number.
1. Calculate the molar mass of hydrogen gas (H2):
The molar mass of one mole of hydrogen gas (H2) is approximately 2.016 g/mol. This value is obtained by adding the atomic masses of two hydrogen atoms (each hydrogen atom has an atomic mass of approximately 1.008 g/mol).
2. Determine the number of moles of hydrogen gas in 35.0 g:
[tex]\[ \text{Number of moles} = \frac{\text{Mass}}{\text{Molar mass}} = \frac{35.0 \, \text{g}}{2.016 \, \text{g/mol}} \][/tex]
3. Calculate the number of hydrogen atoms using Avogadro's number:
[tex]\[ \text{Number of atoms} = \text{Number of moles} \times \text{Avogadro's number} \][/tex]
Now, let's perform the calculations:
[tex]\[ \text{Number of moles} = \frac{35.0 \, \text{g}}{2.016 \, \text{g/mol}} \approx 17.36 \, \text{mol} \][/tex]
Using Avogadro's number [tex](\(6.022 \times 10^{23} \, \text{atoms/mol}\))[/tex], we have:
[tex]\[ \text{Number of atoms} = 17.36 \, \text{mol} \times (6.022 \times 10^{23} \, \text{atoms/mol}) \][/tex]
[tex]\[ \text{Number of atoms} \approx 1.045 \times 10^{25} \, \text{atoms} \][/tex]
Therefore, there are approximately [tex]\(1.045 \times 10^{25}\)[/tex] hydrogen atoms in 35.0 g of hydrogen gas.
what would be the temperature of 0.734 moles of chlorine gas be at 1.83 atmospheres in a 10.2 liter container? (r=0.0821 L·atm/mol·k)
Answer: 310K
Explanation:
Since,
Pressure P = 1.83 atmospheres
Volume of chlorine gas V = 10.2L
Molar gas constant R = 0.0821 L.atm/mol.k)
Number of moles = 0.734 moles
Temperature T(in Kelvin) = ?
Apply ideal gas equation (pV = nRT)
1.83atm x 10.2L= 0.734 moles x 0.0821 L.atm/mol.k x T
18.67 = (0.06026 x T)
T = (18.67 / 0.06026)
T = 310K
Therefore, the new temperature of the chlorine gas is 310K
A student wants to classify some household chemicals by testing them using litmus paper. If she is going to classify these chemicals correctly, which statement will best help her determine if the chemicals are acids or bases? *
if blue litmus paper turns red, the substance has a pH below 7 and is an acid
if blue litmus paper turns red, the substance has a pH above 7 and is a base
if blue litmus paper turns red, the substance has a pH below 7 and is a base
if blue litmus paper turns red, the substance has a pH above 7 and is an acid
The statement which is correct about acids or base is if blue litmus paper turns red, the substance has a pH below 7 and is an acid.
What are acids and bases?Acids are those substances which has a pH value below 7 and bases are those substances which has a pH value greater than 7.
Acids turn blue litmus paper to red color and Bases turn red litmus paper to blue color.
If blue litmus paper turns red, the substance has a pH below 7 and is an acid is true.If blue litmus paper turns red, the substance has a pH above 7 and is a base is incorrect.If blue litmus paper turns red, the substance has a pH below 7 and is a base is also incorrect.If blue litmus paper turns red, the substance has a pH above 7 and is an acid is also incorrect.So correct statement is if blue litmus paper turns red, the substance has a pH below 7 and is an acid.
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I swear is it just me or I struggling with science!
help
Explanation:
The term mutualism refers to a relationship in biology or sociology that is mutually beneficial to two living things. This relationship can be within the species, between living things from two different species, between individuals in a society and between two societies.The predator prey relationship consists of the interactions between two species and their consequent effects on each other. In the predator prey relationship, one species is feeding on the other species. The prey species is the animal being fed on, and the predator is the animal being fed.when organisms compete for resourcesto get waterplease like and Mark as brainliestThere are 231.0 grams of Iron (ll) Hydroxide, Fe(OH)2. How many moles of Fe(OH)2 does that equal?
Explanation:
firstly you find for the molar mass of the iron(ii)hydroxide
and then use this formula
mole=mass/molar mass and then slot in your given values
and then you will get
2.57moles
the answer is 2.57 mole of iron(ii)hydroxide
Generators need a source of energy to produce electricity. Which form of energy is a nonrenewable source of energy?
A.
hydro (water) energy
B.
geothermal energy
C.
fossil fuel
D.
wind energy
Answer:
Explanation:
Fossil fuel is nonrenewable, whereas hydro, wind, solar, and wave power are generally ... depletes its fuel stock but at a relatively slow rate, and geothermal energy (Williamson, ... Future primary energy sources (e.g. nuclear, coal and solar) are primarily ... b. Distributed peak electrical generation, •. c. Distributed electricity ...
Answer: is C fossil fuel
Darwin developed the theory of evolution. Which of these observation is the best evidence for the theory of evolution?
A) Humans have very diverse traits today.
B) There appear to be missing links in the evolutionary chain.
C) Life on earth has been found to date back billions of years.
D) DNA found in older primate fossils resemble those of humans today.
Answer: It's D
Explanation:A and B cant be it and C has nothing to do with it because it doesnt talk about evolution while D does that the older fossils resemble us
When the pressure that a gas exerts
on a sealed container changes
from
torr to 456 torr, the
temperature changes from 150°C
to 75.0°C.
Answer:
554 torr
Explanation:
i got it right on the test.
Answer:
554
Explanation:
What is the pressure in mm of Hg , of a gas mixture that contains 1g of H2, and 8.0 g of Ar in a 3.0 L container at 27°C.
Answer:
4362.4 mmHg
Explanation:
Step 1:
Determination of the number of mole of H2 and the number of mole of Ar.
Molar Mass of H2 = 2x1 = 2g/mol
Mass of H2 = 1g
Number of mole of H2 =?
Number of mole = Mass/Molar Mass
Number of mole of H2 = 1/2 = 0.5 mole
Molar Mass of Ar = 40g/mol
Mass of Ar = 8g
Number of mole of Ar =?
Number of mole = Mass/Molar Mass
Number of mole of Ar = 8/40 = 0.2 mole
Step 2:
Data obtained from the question.
Volume (V) of the mixture = 3L
Temperature (T) = 27°C = 27°C + 273 = 300K
Number of mole (n) of the mixture = 0.5 + 0.2 = 0.7 mole
Gas constant (R) = 0.082atm.L/Kmol
Pressure (P) of the mixture =?
Step 3:
Determination of the pressure of the mixture.
The pressure of the mixture can be obtained as follow:
PV = nRT
P x 3 = 0.7 x 0.082 x 300
Divide both side by 3
P = (0.7 x 0.082 x 300) /3
P = 5.74 atm
Step 4:
Conversion of the pressure obtained from atm to mmHg.
1 atm = 760mmHg
Therefore, 5.74 atm = 5.74 x 760 = 4362.4 mmHg
A chemist has a sample of hydrated Li2SiF6 and it weighs 0.4813 grams. He heats it strongly to drive off the water of hydration, and after heating, he found that the anhydrous compound has a mass of 0.391 grams. What is the percent of water in the hydrate?
Answer:
percentage of water = 18.76%
Explanation:
A chemist has a sample of hydrated Li2SiF6 and it weighs 0.4813 grams.
The overall weight of the compound is 0.4813 grams.
weight of hydrated sample = 0.4813 grams.
weight of anhydrous compound = 0.391 grams
percentage weight of water = mass of water/mass of the hydrated compound × 100
mass of water = mass of hydrated compound - mass of anhydrous compound
mass of water = 0.4813 - 0.391 = 0.0903 grams.
percentage of water = 0.0903/0.4813 × 100
percentage of water = 9.03/0.4813
percentage of water = 18.761687097
percentage of water = 18.76%
Answer:
18.8%
Explanation:
Step 1:
The following data were obtained from the question.
Mass of hydrated Li2SiF6 = 0.4813 g
Mass of anhydrous Li2SiF6 = 0.391 g
Step 2:
Determination of the mass of the water in the hydrate.
Mass of water = (Mass of hydrated Li2SiF6) - (Mass of anhydrous Li2SiF6)
Mass of water = 0.4813 - 0.391
Mass of water = 0.0903 g
Step 3:
Determination of the percentage of water in the hydrate.
The percentage of water = Mass of water/ mass of hydrate x 100
The percentage of water = 0.0903/0.4813 x 100
The percentage of water = 18.8%
Ethanol is increasingly being used as a fuel for cars.
The standard enthalpy change of formation of carbon dioxide is -393 kJmol.
The standard enthalpy change of formation of water is --286 kJmol.
The standard enthalpy change of formation of ethanol is -277 kJmol.
What is the standard enthalpy change of combustion of ethanol?
Answer:
= -522.5\,\, kJmol^{-1}
Explanation:
Firstly, we know that 0.36 g of ethanol burned, so we can convert this into a number of moles.
Using a formula triangle to calculate the number of moles of ethanol in a 0.36 gram sample
Secondly, we can use \Delta H=cm\Delta T to calculate the enthalpy change in the experiment described in the question (ie when 0.008 moles of ethanol is burned).
\Delta H=cm\Delta T = 4.18 x 0.2 x 5
= 4.18 kJ
Lastly, we can use the enthalpy change for the experiment in the question to calculate the enthalpy of combustion (ie when one mole of ethanol is burned).
0.008\,\,moles\,\,ethanol = 4.18kJ
1\,\,mole\,\,ethanol = \frac{1}{0.008} \times 4.18
= -522.5\,\, kJmol^{-1}
Answer:
-522.5
Explanation:
because for the formula i found that.