Answer:gold
Explanation:
For the chemical reaction H2 + CO2 → H2O + CO, the energy contained in the reactants is 394 kJ, and the energy contained in the products is 352 kJ, assuming 1 mol of each substance is present. Which of the following statements is true?
A. 42 kJ is released, and the reaction is exothermic.
B. 42 kJ is absorbed, and the reaction is exothermic. C. 42 kJ is absorbed, and the reaction is endothermic. D. 42 kJ is released, and the reaction is endothermicWhy is rusting a chemical change?
Rusting is a chemical change where iron reacts with oxygen and water to form iron oxide, a new substance with distinct chemical properties. This process signifies a release of energy and is a part of corrosion, differentiating it from mere physical changes.
Rusting is considered a chemical change because it results in the formation of a new substance with different properties compared to the starting materials. When iron is exposed to oxygen and water, a reaction occurs that produces iron oxide, commonly known as rust. This process, known as corrosion, involves not just a change in the appearance of the iron, but also the formation of a new chemical compound with its own distinct properties.
A chemical property of iron is its tendency to combine with oxygen, an observation that can be made when iron begins to rust. The rusting process not only changes the color and texture of the iron but also signifies that energy stored in the reactants has been released during the formation of the rust. Unlike physical changes that do not affect the substance's chemical identity, chemical changes like rusting create a fundamentally different kind of matter.
Name two other compounds with bonding similar to that in hydrogen bromide
30ml of 0.10 NaOh neutralized 25.0ml of HCL determine the concentration of the HCL? PLEASE HELP ME ASAP
ll of the following could be considered reconstruction except :
A. scientists assume an area was once undersea due to the types of rock deposits
B. scientists assume an animal was a meat eater because of the teeth in its fossil
C. scientists assume an animal could climb trees because of its hand structure
D. scientists predict a volcano will erupt in the near future because of current volcanic activity
Answer: -
D. scientists predict a volcano will erupt in the near future because of current volcanic activity
Explanation: -
Reconstruction involves analyzing evidence present to understand what happened before. For example scientists assume an area was once undersea due to the types of rock deposits. The area was under sea before.
Scientists assume an animal was a meat eater because of the teeth in its fossil. Again the animal was before.
Scientists assume an animal could climb trees because of its hand structure . The animal existed before. Now no longer present.
But in D scientists predict a volcano will erupt in the near future because of current volcanic activity, the event of eruption could occur in the future. It has not happened already like in the previous cases.
Properties such as luster, conductivity, and flexibility are used to describe what type of elements
Answer:
A.metals is the correct answer
give an example that shows that gravity affects objects through gases liquids and solids
Help please before 10 it's urgent for my daughter
Answer:
Certainly! Here's an example that demonstrates how gravity affects objects through gases, liquids, and solids:
Explanation:
Consider a balloon filled with helium gas. When the balloon is released, it rises upwards due to the force of gravity acting on it. Gravity pulls the balloon downwards, but the buoyant force exerted by the surrounding air (a gas) is greater than the weight of the balloon, causing it to float or rise in the air.
Now, imagine a similar scenario but with a beach ball floating in water (a liquid). When the beach ball is placed in water, it experiences the force of gravity pulling it downwards. However, the buoyant force exerted by the water is greater than the weight of the beach ball, causing it to float or rise to the surface of the water.
Lastly, let's consider a solid object like a book placed on a table. The force of gravity pulls the book downwards, creating a normal force between the book and the table. This normal force counteracts the force of gravity, preventing the book from falling through the table and keeping it in place.
In all these examples, gravity acts on the objects, whether they are in the form of gases, liquids, or solids. The specific interactions between gravity and the objects depend on the density, buoyancy, and other physical properties of the substances involved.
Gravity's effects can be seen when a helium balloon (gas) rises in the air, an apple (solid) falls and sinks in water (liquid), and a book (solid) is held stationary on a table due to the force of gravity counteracted by the table's support.
Explanation:Gravity affects all objects regardless of whether they're in gas, liquid, or solid states. An example that illustrates gravity's influence through gases, liquids, and solids could involve observing a helium balloon in the air (gas), an apple falling into water (liquid), and a book resting on a table (solid).
In the case of the helium balloon, gravity is acting upon the balloon, but it is also acting upon the surrounding air. Because helium is less dense than air, the balloon rises, yet gravity still holds it within Earth's atmosphere.When an apple falls from a tree and lands in water, gravity causes the apple to fall, and it continues to pull on the apple even when it hits the water's surface, causing it to sink until the buoyant force of the water balances the weight of the apple.A book on a table is subject to gravity, which pulls it downward. The table provides a normal force that counteracts gravity, preventing the book from falling.
What do I need to convert mass of product to ma's of a reactant
To convert mass of a product to mass of a reactant, determine the molar mass of both substances, convert the product's mass to moles, apply the mole ratio, and convert the reactant's moles back to mass.
To convert the mass of a product to the mass of a reactant in a chemical reaction, you need to follow several steps:
First, determine the molar mass of the product.
Use this molar mass to convert the product's mass to moles.
Next, apply the mole ratio from the balanced chemical equation to find out the number of moles of the reactant.
Finally, use the molar mass of the reactant to convert these moles back to mass.
This process involves a sequence of conversions from mass to moles, mole ratio application, and finally, from moles back to mass.
for an experiment, you need 0.10 moles of NaCl for a chemical reaction. how much NaCl must you weigh out?
A. 0.14g
B. 3.2 g
C. 8.2 g
D. 5.8 g
The mass of NaCl needed for the reaction, you can use the molar mass of NaCl and the given number of moles. The molar mass of NaCl is 58.44 g/mol. By multiplying the number of moles (0.10) by the molar mass, you can calculate the mass of NaCl needed, which is approximately 5.844 g. Option D, 5.8 g, is the closest answer.
To calculate the mass of NaCl needed for the reaction, you can use the molar mass of NaCl and the given number of moles. The molar mass of NaCl (sodium chloride) is the sum of the atomic masses of sodium (Na) and chlorine (Cl). The atomic mass of sodium is approximately 22.99 g/mol, and the atomic mass of chlorine is approximately 35.45 g/mol.
Molar mass of NaCl = Atomic mass of Na + Atomic mass of Cl
= 22.99 g/mol + 35.45 g/mol
= 58.44 g/mol
Now, you can use the formula:
Mass = Number of moles × Molar mass
Mass = 0.10 moles × 58.44 g/mol
Mass = 5.844 g
Therefore, the correct answer is closest to 5.8 g, which corresponds to option D. Therefore, you should weigh out 5.8 g of NaCl for the chemical reaction.
Josh was blowing bubbles through a straw into a glass of tap water. As Josh exhaled into the straw, he blew carbon dioxide gas into the water. The harder he blew, the more bubbles entered the water. The more bubbles, the ______________ the solution gas/water solution.. A) warmer B) more dilute C) less concentrated D) more concentrated
Will give brainliest please help ASAP
Choose all that apply.
Gas pressure within a fixed container will increase when ____
A) gas is cooled
B) gas is heated
C) gas volume changes
D) mass of gas is increased
B) Gas is heated, And D) Mass of gas increased.
Gas pressure within a fixed container will increase when gas is heated and also when mass of gas is increased.
Answer: Options B and D
Explanation:
In a closed container, the temperature is proportional to pressure according to the pressure law. When the gas presents in a container, it means that the size of the container remains constant unless/until it is changed by increasing its size or decreasing it.
When the container gets heated, gas particles gains more kinetic energy, moves faster and hits the inner walls of the container. The amount of gas particles also seems to be more.
And so, it hits the container's wall more frequently and with more speed and force. Hence, these make the gas pressure in the container to increase. According to the Boyle’s law,
[tex]p V=n R T[/tex]
Where, p – pressure, V – volume, n – no. of moles, R – gas constant, T – temperature.
This also tells the reason how the gas pressure increases when the amount of gas and temperature get increased.
A 100 meter dash was held with 20 contestants. The best time was 10.7 seconds, and the worst time was 15.3 seconds. Only the fastest 10 contestants advance to the final race. Which measure of central tendency should be used to calculate the cutoff time for the final race? A. median B. mode C. mean D. range
Answer:
median
Explanation:
study island i got it right
Answer:
median
Explanation:
An electromagnetic wave that has a lower frequency than infrared radiation will have ____ than the infrared radiation. longer wavelength and higher energy longer wavelength and lower energy shorter wavelength and higher energy shorter wavelength and lower energy
The answer is longer wavelength and lower energy.
what are the four main spheres of the earth system
The melting and boiling points of a substance are independent of
A.
rate of heat change.
B.
mass.
C.
volume.
D.
all of these
please just give the laginitmit awser dont go all into deatail and or explain it
Answer:
D.
all of these
what is the mass of 5.0 cm^3 piece of copper having a density of 8.96 g/cm^3
Answer:
The mass of copper piece is 44.8 grams
Explanation:
Density is defined as amount of mass present in the unit volume of the substance.
Mathematically written as:
[tex]\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}[/tex]
We are given:
Density of copper, d =[tex]8.96 g/cm^3[/tex]
Mass of copper piece = M
Volume of the copper piece = V = [tex] 5.0 cm^3[/tex]
Putting values in above equation, we get:
[tex]8.96 g/cm^3=\frac{M}{ 5.0 cm^3}[/tex]
[tex]M=8.96 g/cm^3\times 5.0cm^3=44.8 g[/tex]
Hence, the mass of copper piece is 44.8 grams
There are islands in the ocean that are growing larger. The Hawaiian Islands are good examples of this. The reason that the islands were formed and are still growing is A) they were produced by drought. B) they were produced by volcanoes. C) they were produced by hurricanes. D) they were produced by earthquakes.
An air mass of volume 6.5 x 10 to the fifth L starts at sea level, where the pressure is 775 mm HG. It rises up a mountain where the pressure is 622 mm HG. Assuming no change in temperature, what is the volume of the air mass?
table salt and water are examples of
Table salt (sodium chloride) and water are two fundamental examples of chemical compounds with distinct properties and essential roles in our daily lives. While table salt is ionic and dissolves easily in water, water itself is a covalent compound with unique properties that are vital for sustaining life and various industrial applications.
Table salt (sodium chloride, NaCl) and water (H2O) are examples of chemical compounds, which are formed when two or more elements combine in fixed proportions through chemical bonding. Here's an explanation of each:
Table Salt (Sodium Chloride, NaCl):
Table salt is a common chemical compound that consists of two elements, sodium (Na) and chlorine (Cl). Sodium is a highly reactive metal, and chlorine is a toxic, greenish-yellow gas. However, when these elements chemically react, they combine to form the stable compound sodium chloride (NaCl). Sodium donates one electron to chlorine, forming a positively charged sodium ion (Na+) and a negatively charged chloride ion (Cl-).
These oppositely charged ions are held together by ionic bonds due to electrostatic attraction. Table salt is a crystalline solid with a distinct salty taste and is commonly used to season food and preserve it. It is highly soluble in water, and when dissolved, it dissociates into its constituent ions, making it an electrolyte that conducts electricity in solution.
Water (H2O):
Water is a vital chemical compound consisting of two hydrogen (H) atoms covalently bonded to one oxygen (O) atom. Covalent bonds involve the sharing of electrons, resulting in a molecule with a bent, V-shaped geometry. Water is unique due to its high polarity, meaning it has a partial positive charge near the hydrogen atoms and a partial negative charge near the oxygen atom.
This polarity results in several of water's essential properties, such as its ability to form hydrogen bonds, which give water a high heat capacity, surface tension, and excellent solvent properties. Water is essential for life, serving as the universal solvent in which many biochemical reactions occur. It's also crucial for regulating temperature and maintaining life processes in living organisms.
For more such information on: table salt
https://brainly.com/question/24642102
#SPJ12
what is the approximate ratio of neutrons to protons in a nucleus of radon -222
More protons in the nucleus need more neutrons to bind the nucleus together. The graph below is a plot of the number of neutrons versus the number of protons in various stable isotopes. The stable nuclei are in the pink band known as the belt of stability. They have a neutron/proton ratio between 1:1 and 1.5.
The ratio of neutrons to protons in Radon-222 has been found to be 1.58.
The radon has been the radioactive element. The atomic number of the element has been 222. The element has been consisted of 86 protons.
The number of neutrons and protons has been the mass of the nucleus and has been consisted of the atomic mass of the element. In an isotope, the element has 222 as the atomic number.
Since. Atomic number = Neutrons + Protons
222 = Neutrons + 86
Neutrons = 136
The ratio of neutrons to protons can be given as:
[tex]\rm \dfrac{Neutrons}{Protons}[/tex] = [tex]\rm \dfrac{136}{86}[/tex]
[tex]\rm \dfrac{Neutrons}{Protons}[/tex] = 1.58
The ratio of neutrons to protons in Radon-222 has been found to be 1.58.
For more information about neutrons and protons, refer to the link:
https://brainly.com/question/15916785
Which of the following is an example of a population?
Question 7 options:
all of the western diamondback rattlesnakes in Big Bend National Park
all plants and animals in Grand Canyon National Park
all leopard frogs in the world
all of the trees in Yellowstone National Park
In biology, a population is made up of all individuals of a specific species within a certain area. Thus, the example that best fits this definition is all of the western diamondback rattlesnakes in Big Bend National Park.
Explanation:In biology, a population consists of all the individuals of a certain species living within a specific area. Therefore, the best example of a population among the options provided is all of the western diamondback rattlesnakes in Big Bend National Park. This is because this group contains only one species (western diamondback rattlesnakes) and is limited to a specific area (Big Bend National Park).
Alternatively, the other options contain either multiple specie (all plants and animals in Grand Canyon National Park and all of the trees in Yellowstone National Park) or include a species that is not confined to a specific area or region (all leopard frogs in the world).
Learn more about Population here:https://brainly.com/question/15889243
#SPJ6
Where does subduction happen?
Balance this compound
Answer: The balanced chemical equation is given by,
[tex]2C_2H_6+7O_2\rightarrow 4CO_2+6H_2O[/tex]
Explanation:
[tex]C_2H_6+O_2\rightarrow CO_2+H_2O[/tex]
Law of conservation of mass states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
This also means that total mass on the reactant side must be equal to the total mass on the product side.
So, the balanced chemical equation is given by, will writing stoichiometric coefficient 2 in front of ethane , 7 in front of oxygen , 4 in front of carbon dioxide gas and 6 in front of water.
[tex]2C_2H_6+7O_2\rightarrow 4CO_2+6H_2O[/tex]
According to reaction, 2 moles of ethane reacts with 7 moles of oxygen to give 4 moles f carbon dioxide gas and 6 moles of water.
Which bear describes a chain reaction associated with nuclear reaction
Use the particle theory of matter to explain why icing sugar dissolves more rapidly than granular sugar.
Icing sugar dissolves in water faster than granular sugar because it has a larger surface area, which enhances interactions with solvent molecules, thus speeding up dissolution. Stirring and temperature also affect the rate of dissolution but icing sugar's fine particles inherently dissolve quicker.
Using the particle theory of matter, we can explain why icing sugar dissolves more rapidly than granular sugar. The rate at which a solute dissolves is influenced by the surface area exposed to the solvent. Icing sugar, being finely ground, has a much larger surface area compared to granuler sugar, allowing for more interactions between the sugar particles and the water molecules, leading to a faster rate of dissolution.
Agitation of the solution can also increase the rate at which sugar dissolves. Stirring introduces fresh solvent molecules to the solute, enhancing dissolution by preventing saturation at the interface. This principle applies to both icing and granular sugars but is more pronounced with larger particles like those found in granular sugar.
The dissolving process, or rate of dissolution, is enhanced not only by increasing surface area and agitation but also by temperature. Hot water will dissolve sugar faster than cold water due to the increased energy, which in turn increases the frequency and energy of collisions between solvent and solute particles.
It is safe to thaw frozen foods at room temperature true or false
how many moles of hcl are produced from a reaction with 6.2 moles of h2 given the following equation
How many atoms of oxygen are in one formula unit of Al2(SO4)3? 4 6 7 12
What is the name of the compound Cr2(CO3)3?
Which of the following contains both ionic and covalent bonding?
NaClO
NO2
FeBr3
HI
Help with chemistry hw?
1) We don't actually need to solve this, because we can tell by eye-balling this; however, let's solve it anyway to go over the steps.
At STP, or standard temperature and pressure, a mole of gas always has a volume of 22.4 L.
We have 48.6 g [tex]CO_2[/tex]. Using the molar mass of carbon dioxide, we find the number of moles
[tex]48.6 \ g \ CO_2 \ * \dfrac{1 \ mol \ CO_2}{44.01 \ g \ CO_2} = 1.10 \ CO_2[/tex].
To get the volume, we write
[tex]1.10 \ mol \ CO_2 * \dfrac{22.4 \ L}{mol} = 24.7 \ L \ CO_2[/tex].
2) We have 0.179 g of this gas taking up 1 L.
That means we have [tex] \frac{1}{22.4} \ mol[/tex] of this gas, because one mole of a gas at STP takes up 22.4 L.
If [tex]\frac{1}{22.4} \ mol=0.179 g[/tex], we can solve to find its molar mass and then its identity.
[tex](22.4)(0.179) \ \dfrac{g}{mol} = 4.00 \ \dfrac{g}{mol} [/tex]
He has this molar mass, so we know the identity of the gas is He.
3)
1. This is a decomposition reaction of the form AX ⇒ A + X.
2. ΔH refers to the change in enthalpy in a reaction. For a positive value, the reaction is endothermic; for a negative value, it is exothermic. An endothermic reaction requires energy added to run the reaction, so when this is the case, we write that KE is a reactant.
To find the value for enthalpy, we use known values to calculate 572 kJ, meaning the reaction is endothermic. We write KE as a reactant. (You can also find enthalpy relatively, which is useful when you don’t have the known values for your calculation).
3. The Law of Conservation of Mass states that in a closed system like a chemical reaction, matter (and thus mass) can neither be created nor destroyed. The Law of Conservation of Energy states that energy can never be created or destroyed. Thus, all reactants and products, including energy, must be balanced in a thermochemical equation.
4) We need to write a balanced equation for this reaction.
[tex]2H_2O = 2H_2+O_2[/tex]
Next, we go from grams to moles.
[tex]1 \ mol \ H_2O = 18.016 \ g \ H_2O[/tex]
[tex]38.0 \ g \ H_2O * \dfrac{1 \ mol \ H_2O}{18.016 \ g \ H_2O} = 2.11 \ mol \ H_2O[/tex].
We use the same process to determine there are [tex]1.98 \ mol \ H_2[/tex].
That means that for 2.11 moles of water, we get 1.98 moles of diatomic hydrogen. There are two moles of diatomic hydrogen per mole of diatomic oxygen here in the balanced equation, so we write
[tex]1.98 \ mol \ H_2 * \dfrac{1 \ mol \ O_2}{2 \ mol H_2} = 0.99 \ mol \ O_2[/tex]
[tex]0.99 \ mol \ O_2 * \dfrac{32.00 \ g \ O_2}{mol \ O_2 } = 32.00 \ g \ O_2[/tex]
5) [tex]1 \ g \ H_2 = 2.016 \ g \ H_2[/tex]
[tex]12.0 \ g \ H_2 * \dfrac{1 \ mol \ H_2}{2.016 \ g } =5.95 \ mol \ H_2[/tex]
One mole of a gas at STP has a volume of 22.4 L.
5.95 mol * 22.4 L/mol = 133 L
6) [tex]1 \ g \ H_2 = 2.016 \ g \ H_2[/tex]
[tex]2 \ mol \ H_2 * \dfrac{2.016 \ g \ H_2}{1 \ mol \ H_2}=4 \ mol \ H_2[/tex]
7) [tex]1 \ mol \ H_2O = 18.016 \ g \ H_2O[/tex]
[tex]150.0 \ g \ H_2O * \dfrac{1 \ mol \ H_2O}{18.016 \ g \ H_2O} = 8.326 \ mol \ H_2O[/tex]
8) We first balance this to get [tex]2H_2O = 2H_2 + O_2[/tex]. There are two moles of water per mole of diatomic oxygen.
9) To produce 8.0 mol diatomic hydrogen, we use the balanced equation from above.
We have a one-to-one ratio of water to diatomic hydrogen, so we need 8.0 mol water.
10) Again, using our balanced equation, we first find the number of moles of water.
[tex]1 \ mol \ H_2O = 18.016 \ g \ H_2O[/tex]
[tex]50.0 \ g \ H_2O * \dfrac{1 \ mol \ H_2O}{18.016 \ g \ H_2O} = 2.78 \ mol \ H_2O[/tex]
We have that there are two moles of water for every one mole of diatomic oxygen, so we have 1.39 mol diatomic oxygen.
This is [tex]1.39 \ mol * \dfrac{32.00 \ g \ O_2}{1 \ mol \ O_2} = 44.5 \ g \ O_2[/tex]