Final answer:
In Chemistry, significant figures represent precision in measurements. The number of significant figures varies for each measurement based on the rules of counting significant figures, considering zeros as either placekeepers or significant values.
Explanation:
The subject of this question is Chemistry, particularly focusing on significant figures which are crucial for representing precision in measurements. Let's determine the number of significant figures in each given measurement using the rules for counting significant figures:
0.0908 has three significant figures (leading zeros are not significant).
340.02 has five significant figures (zeros between non-zero digits are significant).
5420 has three significant figures, assuming the last zero is not significant unless otherwise stated (if in scientific notation, it would clarify).
12.90 has four significant figures (trailing zeros in a decimal are significant).
3.09 x 10^8 has three significant figures (all digits in the coefficient are significant).
0.79 has two significant figures (leading zeros are not significant).
0.02050 has four significant figures (trailing zeros in a decimal number are significant).
0.009 has one significant figure (leading zeros are not significant).
4709 has four significant figures (all non-zero digits are significant).
Molecules of two substances at the same temperature have the same:
A) average kinetic energy.
B) heat content.
C) distance between the molecules.
D) average potential energy.
Answer:
heat content
Explanation:
the kinetic energy , distance between molecules, and potential energy are all depending on the substance
Which one of the following is a common acid? A. Antacid
B. Wasking soda
C. Aspirin
D. Soap
FOLLOW ME FOR CLEARING YOUR NEXT DOUBT
Answer:
C. Aspirin
Explanation:
If you are using A pex, this is the correct answer.
Reasoning: Soap is not an acid so thats out of the question. I'm not sure if washing soda or antacid are acidic but even if they were, Aspirin is definitely an acid and is way more commonly used than those two.
Can red cabbage juice indicator be used to determine the strength of acids and bases? Explain.
The strong acid and strong base has high rate constant of dissociation. Weak acid and base are the one whose rate constant for the dissociation is low, they do not dissociate readily in water. The red cabbage juice can be used to determine the strength of acids and bases.
What are acid and base?Acid is a solution which releases H⁺ hydrogen ion when dissolved in water. Base are the solution which releases hydroxide ion OH⁻ ion when dissolved in water
Red cabbage juice contain a pigment called anthocyanin. Acidic solutions turns purple color of anthocyanin red. Basic solutions turns purple color of anthocyanin greenish-yellow. There will be no change in color in neutral solution.
Therefore, red cabbage juice can be used to determine the strength of acids and bases.
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Describe the electrolysis of molten lithium chloride to produce lithium and chlorine gas.
Answer:
it mainly depends what state of lithium chloride that you use to electrolysis, if you choose the aqueous state of lithium chloride then you'll have a produce of chlorine and oxygen at the anode, lithium and hydrogen is produce at the cathode but lithium will react with water to form lithium hydroxide
Explanation:
Final answer:
The electrolysis of molten lithium chloride results in the formation of lithium metal at the cathode and chlorine gas at the anode, involving the direct conversion of chemical energy into electrical energy through electrolysis.
Explanation:
The question is about describing the electrolysis of molten lithium chloride to produce lithium and chlorine gas. The process of electrolysis involves passing an electric current through molten lithium chloride (LiCl), resulting in the formation of lithium metal (Li) and chlorine gas (Cl₂). This process takes place in an electrolytic cell.
At the cathode (negative electrode), lithium ions (Li⁺) gain electrons (e⁻) to form lithium metal (Li).At the anode (positive electrode), chloride ions (Cl⁻) lose electrons to form chlorine gas (Cl₂).Overall reaction: 2LiCl(l) → 2Li(s) + Cl₂(g)
At the cathode: Li⁺ + e⁻ → Li(s)
At the anode: 2Cl⁻ → Cl₂(g) + 2e⁻
These reactions demonstrate the principle of electrochemistry where chemical energy is converted into electrical energy, and vice versa. The electrolysis of molten lithium chloride is an efficient way to produce pure lithium metal and chlorine gas, which have various applications in industries.
Which statement describes a reaction at equilibrium?
1. The mass of the products must equal the mass of the reactants
2. The entropy of the reactants must equal the entropy of the products
3. The rate of formation of the products must equal the rate of formation of the reactants.
4. The number of moles of the reactants must equal the number of moles of the products.
Answer:
3. The rate of formation of the products must equal the rate of formation of the reactants.
Explanation:
The reaction at the equilibrium represents the rate of formation of the products that is equivalent to the rate of formation of the reactants.
What is the reaction?It is arise at the equilibrium at the time when the amounts of reactants or products should be same. The Chemical equilibrium refers to the dynamic process that represent the rate of formation of products via the forward reaction i.e. equivalent to the rate where the products should be reform reactions via the reverse reaction.
hence, the option 3 is correct.
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In a closed system at 40°C, a liquid has a vapor
pressure of 50 kPa. The liquid's normal boiling
point could be
(1) 10°C
(3) 40°C
(2) 30°C
(4) 60°C
The question pertains to the normal boiling point of a liquid, which is the temperature at which its vapor pressure equals 1 atm (101.3 kPa). Given the vapor pressure is 50 kPa at 40°C, the normal boiling point must be higher than 40°C, making 60°C the correct answer.
Explanation:The question concerns the normal boiling point of a liquid, which is defined as the temperature at which a liquid’s vapor pressure equals the atmospheric pressure. In a closed system at 40°C, a liquid has a vapor pressure of 50 kPa, but the normal boiling point occurs when its vapor pressure reaches 101.3 kPa, the typical atmospheric pressure. Given that the vapor pressure of the liquid at 40°C is less than 101.3 kPa, and knowing that vapor pressure increases with temperature until it reaches atmospheric pressure (allowing the liquid to boil), the liquid's normal boiling point must be higher than 40°C. Therefore, the answer is (4) 60°C, as it’s the only option provided that is higher than 40°C.
What is the only thing held constant in a combined gas law problem?
Only the amount of gas is held constant.
Are scientific theories all proven facts?
Answer:
Any scientific theory must be based on a careful and rational examination of the facts. Facts and theories are two different things. In the scientific method, there is a clear distinction between facts, which can be observed and/or measured, and theories, which are scientists' explanations and interpretations of the facts.
Explanation:
A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results.
6-8 , what does those symbols mean ?
Answer:
The weird one that looks like a B is a symbol for a beta ray.
"He" and the infinity looking a represents an alpha particle.
6= Beta ray
7 & 8= alpha particle
How much heat is required, in calories, to raise the temperature of 57.8g of silver from 17.0oC to 43.5oC, if the specific heat of silver = 0.057cal / goC?
Answer:
83.60oC per cal
Explanation:
The amount of heat required to raise the temperature of 57.8g of silver from 17.0°C to 43.5°C is 87.31 calories.
How to calculate energy?The energy required to raise the temperature of a substance can be calculated using the following formula:
Q = m × c × ∆T
Where;
Q = quantity of heat absorbed or releasedm = mass of the substancec = specific heat capacity∆T = change in temperatureQ = 57.8 × 0.057 × (43.5 - 17)
Q = 87.31calories
Therefore, the amount of heat required to raise the temperature of 57.8g of silver from 17.0°C to 43.5°C is 87.31 calories.
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0.65 moles of O2 originally at 85°C is cooled
such that it now occupies 8.0 L at 40.°C.
What is the final pressure exerted by the gas?
Answer:
2.09 atm
Explanation:
We can solve this problem by using the equation of state for an ideal gas, which relates the pressure, the volume and the temperature of an ideal gas:
[tex]pV=nRT[/tex]
where
p is the pressure of the gas
V is its volume
n is the number of moles
R is the gas constant
T is the absolute temperature
In this problem we have:
n = 0.65 mol is the number of moles of the gas
V = 8.0 L is the final volume of the gas
[tex]T=40C+273=313 K[/tex] is the temperature of the gas
[tex]R=0.082 atm L mol^{-1} K^{-1}[/tex] is the gas constant
Solving for p, we find the final pressure of the gas:
[tex]p=\frac{nRT}{V}=\frac{(0.65)(0.082)(313)}{8.0}=2.09 atm[/tex]
0.65 moles of O₂ at 40. °C and 2.1 atm occupy a volume of 8.0 L.
0.65 moles (n) of O₂ originally at 85°C is cooled. It occupies 8.0 L (V) at 40.°C (T). We will convert the final temperature to Kelvin using the following expression.
[tex]K = \°C + 273.15 = 40\°C + 273.15 = 313 K[/tex]
We can calculate the final pressure (P) exerted by the gas using the ideal gas equation.
[tex]P \times V = n \times R \times T\\\\P = \frac{n \times R \times T}{V} = \frac{0.65 mol \times (\frac{0.082atm.L}{mol.K} ) \times 313K}{8.0L} = 2.1 atm[/tex]
0.65 moles of O₂ at 40. °C and 2.1 atm occupy a volume of 8.0 L.
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You’re at the zoo and have a big red 1.80 L helium balloon. The barometric pressure today is 785 mmHg. Then you hear the roar of a lion. Startled, you accidentally release the balloon. It flies away. By the time it reaches the clouds, the atmospheric pressure that high is only 3.00 atmospheres. What would the volume of the balloon up there? (Temperature is constant)
Answer:
0.62 L
Explanation:
Step 1:
Data obtained from the question.
Initial Volume (V1) = 1.80 L
Initial pressure (P1) = 785 mmHg
Final pressure (P2) = 3.00 atm
Final volume (V2) =?
Step 2:
Conversion of the pressure in mmHg to atm.
It is important to express the initial and the final pressure in the same unit. Either express both in atm or in mmHg. What ever the case is, we'll still arrive at same answer. Here, we shall be converting from mmHg to atm. This is illustrated below:
760mmHg = 1atm
Therefore, 785 mmHg = 785/760 = 1.03 atm
Step 3:
Determination of the final volume. This is illustrated below.
We shall be applying the Boyle's law equation since the temperature is constant.
P1V1 = P2V2
Initial Volume (V1) = 1.80 L
Initial pressure (P1) = 1.03 atm
Final pressure (P2) = 3.00 atm
Final volume (V2) =?
P1V1 = P2V2
1.03 x 1.8 = 3 x V2
Divide both side by 3
V2 = (1.03 x 1.8) /3
V2 = 0.62 L
Therefore, the new volume of the balloon is 0.62 L
Answer:
The volume of the balloon up there will be 0.618 L
Explanation:
Given:
V₁ = 1.8 L
P₁ = 785 mmHg = 1.03 atm
P₂ = 3 atm
Question: What would the volume of the balloon up there, V₂ = ?
According the ideal gas law:
PV = nRT
However, in this case, the number of moles of helium balloon is constant. The temperature will also be assumed to be constant. Therefore, the expression of the ideal gases is as follows:
P₁V₁ = P₂V₂
Solving for V₂
[tex]V_{2} =\frac{P_{1}V_{1} }{P_{2} } =\frac{1.03*1.8}{3} =0.618L[/tex]
The number 40 in the name calcium-40 represents
A. the atomic number
B. the number of protons in the atom
C. the sum of the protons and neutrons
D. none of these
Answer:
A. the atomic number
Explanation:
It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth.
What mass, in grams, of aluminum hydroxide will be required to prepare the 4 L of a 1.75 M solution?
Answer: 0.53g
Explanation:
No of moles= volume ×molarity/1000
We have the volume and the molarity
Volume=4L
Molarity=1.7M
No of moles = 4×1.7/1000
No of moles= 0.0068moles
Remember also that
No of moles= mass given/molar mass
Molar mass of Al(OH)3
Al= 27
O=16
H=1
Molar mass = Al+(O+H)3
Molar mass= 27+(16+1)3
Molar mass= 27+(17)3
Molar mass = 27+51
Molar mass= 78g/mol
To get the mass
Mass given = no of moles × molar mass
Mass= 0.0068×78
Mass= 0.53g
1- A gas occupies a volume of 4.0 L at 2.5 kPa. What volume will the gas occupy at 20.0 kPa?
I
Answer:
0.5 L
Explanation:
V1 (initial volume) = 4 L
P1 (initial pressure) = 2.5 kPa
P2 (final pressure) = 20 kPa
V2 (final volume) = ?
Use Boyle's law P1V1 = P2V2, to find the the final volume
P1V1 = P2V2
2.5 x 4 = 20 x V2
Divide both side by 20
V2 = (2.5 x 4)/20
V2 = 0.5 L
Answer: 0.5L
Explanation:
Using Boyle's law
P1V1=P2V2
P1= 2.5kpa
V1= 4l
V2= ?
P2= 20.0kpa
Substitute the value into this formula
P1V1=P2V2
2.5×4=20×V2
Cross multiply
2.5×4=20V2
V2= 2.5×4/20
V2= 80/2.5
V2= 0.5L
So 0.5L of gas will occupy 20.0kpa
Harry uses a pulley to pull up a bucket of water from a well. He uses chemical energy in his body to apply mechanical energy to the system. Which of the following energy transformations also occurs as the bucket rises?
In pulling up a bucket of water, Harry uses chemical energy converted into mechanical energy, which transforms into gravitational potential energy as the bucket rises.
Explanation:When Harry pulls up the bucket of water from the well using a pulley, a number of energy transformations occur. Initially, he uses the chemical energy in his body (obtained from the food he eats) to apply mechanical energy to the system (pulley and bucket). As the bucket begins to rise, the mechanical energy is transformed into gravitational potential energy. This is similar to water at a higher elevation having a higher potential energy than water at a lower elevation.
This process demonstrates a key principle in physics: energy is conserved and can be transferred or transformed from one form to another, but is never lost. So in this case, the chemical energy in Harry's muscles is converted into mechanical energy, which in turn is transformed into gravitational potential energy as the bucket is lifted higher in the well.
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10 POINTS PLEASE HELP ASASP WILL MARK BRANLIEST
Which of the following statements regarding the influence of organisms on rocks is true?
A.
Rocks can be neither formed nor altered by the activity of organisms.
B.
Rocks can be formed and altered by the activity of organisms.
C.
Rocks can only be altered by the activity of organisms.
D.
Rocks can only be formed by the activity of organisms.
Answer:
B. Rocks can be formed and altered by the activity of organisms
Explanation:
How is the solubility of carbon dioxide gas in water increased?
by stirring the mixture
by increasing the pressure
by using more solvent
by increasing the temperature
Answer:
by increasing the temperature
The Volume of a certain gas is 29.3 liters at STP. What would be the volume of the same gas at 1.39 atmospheres and -23.0oC? (R= 0.0821 L.atm/mol.k)
Answer:
V₂ =19.30 L
Explanation:
Given data:
Initial volume of gas = 29.3 L
Initial temperature = standard = 273 K
Initial pressure = standard = 1 atm
Final volume = ?
Final temperature = -23°C (-23+273 =250 K)
Final pressure = 1.39 atm
Solution:
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 1 atm × 29.3 L × 250 K / 273 K × 1.39 atm
V₂ = 7325 atm.L.K / 379.47 K.atm
V₂ =19.30 L
The graph that BEST represents the speed of sound relative to the density of the medium it is traveling through is A) A B) B C) C D) D
Answer:
B .
Explanation:
Answer:
D
Explanation:
I tried it and it worked :)
Caculate the pH of a solution that has a hydrogen ion concentration of 0.0025
Answer:
The pH of the solution is 2.60.
Explanation:
The pH gives us an idea of the acidity or basicity of a solution. More precisely, it indicates the concentration of H30 + ions present in said solution. The pH scale ranges from 0 to 14: from 0 to 7 corresponds to acid solutions, 7 neutral solutions and between 7 and 14 basic solutions. It is calculated as:
pH = -log (H30 +)
pH= -log (0,0025)
pH=2.60
At constant volume, the pressure of a gas is 755 kPa at 30.0 degrees C. What is the temperature of the gas if the pressure is decreased to 252 kPa?
Answer:
T₂ = 101.13 K OR
- 172.02 °C
Explanation:
Given data:
Initial pressure of gas = 755 Kpa
Initial temperature = 30.0°C
Final temperature = ?
Final pressure = 252 Kpa
Solution;
Initial temperature = 30.0°C (30+273 = 303 K)
According to Gay-Lussac Law,
The pressure of given amount of a gas is directly proportional to its temperature at constant volume and number of moles.
Mathematical relationship:
P₁/T₁ = P₂/T₂
Now we will put the values in formula:
755 Kpa / 303 K = 252 Kpa / T₂
T₂ = 252 Kpa ×303 K / 755 Kpa
T₂ = 76356 KPa.K / 755 Kpa
T₂ = 101.13 K
Kelvin to °C:
101.13 K - 273.15 = - 172.02 °C
What is the difference between the 3 types of solar eclipses
based on how they occur? ILL OUT YOU AS BRANILEST
Answer:
Hi There The correct answer There are 3 kinds of solar eclipses: total, partial, and annular. There is a rare hybrid that is a combination of an annular and a total eclipse.
Hope it helps!
Answer:
There are 3 kinds of solar eclipses: partial, total, and annular.
Total EclipseA total solar eclipse occurs when the Moon completely covers the Sun, as seen from Earth.
Partial EclipseThis one happens when the moon covers part of the sun.
Annular EclipseAn annular solar eclipse occurs when the Moon appears smaller than the Sun as it passes centrally across the sun and leaves a ring of light around the moon.
Give Brainliest if you please
What is the mass of oxygen that can be produced from 2.79 moles of lead(ll) nitrate
1.38 moles of oxygen
Explanation:
Thermal decomposition of Lead (II) nitrate is shown by the balanced equation below;
2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂
The mole ration of Lead (II) nitrate to oxygen is 2: 1
Therefore 2.76 moles of Lead (II) nitrate will lead to production of? moles of oxygen;
2: 1
2.76: x
Cross-multiply;
2x = 2.76 * 1
x = 2.76 / 2
x = 1.38
An organism's unique characteristics affect the individual's ability to survive in its environment. true or false
Answer:
True
Explanation:
Therefore, the independent variable was
and the dependent
variable was
In a study or experiment, the independent variable is what the researcher manipulates and the dependent variable is the response being measured. An example of this would be studying the effect of sunlight (independent variable) on plant growth (dependent variable).
Explanation:In any experiment or study, the independent variable is the factor that the researcher manipulates or chooses intending to cause a change. It's the variable you have control over. The outcome of this change is observed and measured in the dependent variable. The dependent variable responds to the change you made to the independent variable. For example, if you were studying the effect of varying amounts of sunlight on plant growth. The amount of sunlight would be the independent variable (as you are controlling the amount each plant gets), and the plant growth would be the dependent variable (as you measure it after).
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Answer:
first part of the problem: temperture and volume
second part: tempture and volume
hope this helps
Explanation:
How many representative particles are in 1.45 g of a molecular compound with a molar mass of 237 g?
Answer: 3.68 x 10^21 particles
Explanation:
Based on Avogadro's law:
1 mole of any substance has 6.02 x 10^23 atoms
Since 1 mole is the same as molar mass of a substance
237 g = 6.02 x 10^23 atoms
1.45g = Z atoms
To get the value of Z, cross multiply:
(Z atoms x 237g) = (6.02 x 10^23 atoms x 1.45g)
237Z = 8.729 x 10^23
Z = (8.729 x 10^23 / 237)
Z = 3.68 x 10^21
Thus, there are 3.68 x 10^21 representative particles in 1.45 g of the molecular compound.
To find the number of representative particles in 1.45 g of a substance with a molar mass of 237 g/mol, first calculate the number of moles by dividing the mass by the molar mass, then multiply by Avogadro's number. The calculation shows there are approximately 3.69 × 10²± representative particles.
Explanation:To calculate the number of representative particles in 1.45 g of a molecular compound with a molar mass of 237 g/mol, we need to use Avogadro's number and the concept of molar mass.
First, we determine the number of moles in 1.45 g:
Number of moles = mass (g) / molar mass (g/mol) = 1.45 g / 237 g/mol.
After finding the number of moles, we use Avogadro's number (6.02 × 10²³ particles/mol) to find the number of representative particles:
Number of particles = number of moles × Avogadro's number.
Therefore, we would calculate:
1.45 g / 237 g/mol = 0.0061180 moles.
Number of particles = 0.0061180 moles × 6.02 × 10²³ particles/mol.
After performing the multiplication, we find:
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15L tank of gas is contained at a high pressure of 8.20 •10 ^4 torr. The tank is opened and the gas expands into an empty chamber with a volume of 6• 10^4 L
The question is incomplete. The complete question is:
15L tank of gas is contained at a high pressure of [tex]8.20\times 10^4 torr[/tex]. The tank is opened and the gas expands into an empty chamber with a volume of [tex]6\times 10^4 L. What is the final pressure if the temperature remains constant.
Answer: 20.5 torr
Explanation:
To calculate the new pressure, we use the equation given by Boyle's law. This law states that pressure is directly proportional to the volume of the gas at constant temperature.
The equation given by this law is:
[tex]P_1V_1=P_2V_2[/tex]
where,
[tex]P_1\text{ and }V_1[/tex] are initial pressure and volume.
[tex]P_2\text{ and }V_2[/tex] are final pressure and volume.
We are given:
[tex]P_1=8.20\times 10^4torr\\V_1=15L\\P_2=?\\V_2=6\times 10^4L[/tex]
Putting values in above equation, we get:
[tex]8.20\times 10^4\times 15L=P_2\times 6\times 10^4L\\\\P_2=20.5torr[/tex]
Thus new pressure will be [tex]20.5torr[/tex]
Calculate the pH of a solution prepared by mixing 25.00 mL of 0.155 M Ca(OH)2
solution with 35.00 mL of 0.112 M HCl solution
Answer:
pH of solution is: 12.82
Explanation:
The reaction of hydrochloric acid with calcium hydroxide is:
Ca(OH)₂ + 2 HCl → H₂O + CaCl₂
Where 2 moles of hydrochloric acid react with 1 mole of calcium hydroxide
Moles of HCl and moles of Ca(OH)₂ are:
Moles HCl:
0.02500L × (0.155mol / L) = 3.875x10⁻³moles HCl
Moles of Ca(OH)₂:
0.03500L × (0.112mol / L) = 3.92x10⁻³moles Ca(OH)₂
Moles of Ca(OH)₂ that react are:
3.875x10⁻³moles HCl × (1 mol Ca(OH)₂ / 2 mol HCl) = 1.9375x10⁻³ mol Ca(OH)₂
Thus, moles of Ca(OH)₂ that remain are:
3.92x10⁻³moles Ca(OH)₂ - 1.9375x10⁻³ mol Ca(OH)₂ = 1.9825x10⁻³ mol Ca(OH)₂
Moles of OH⁻ are:
1.9825x10⁻³ mol Ca(OH)₂ × (2mol OH⁻ / 1mol Ca(OH)₂) = 3.965x10⁻³ mol OH⁻
As volume is 25mL + 35mL = 60mL ≡ 0.060L. Molar concentration of OH⁻ is:
3.965x10⁻³ mol OH⁻ / 0.060L = 0.066M OH⁻.
pOH = -log [OH⁻]
pOH = 1.18
pH = 14-pOH
pH of solution is: 12.82
Answer:
pH = 12.80
Explanation:
Step 1: data given
Volume of a 0.155 M Ca(OH)2 = 25.00 mL = 0.025 L
Volume of a 0.112 M HCl = 35.00 mL = 0.035 L
Step 2: The balanced equation
Ca(OH)2 + 2HCl → CaCl2 + 2H2O
Step 3: Calculate moles
Moles = molarity * volume
Moles Ca(OH)2 = 0.155M * 0.025 L
Moles Ca(OH)2 = 0.003875 moles
Moles HCl = 0.112 M * 0.035 L
Moles HCl = 0.00392 moles
Step 4: Calculate the limiting reactant
For 1 mol Ca(OH)2 we need 2 moles HCl to produce 1 mol CaCl2 and 2 moles H2O
HCl is the limiting reactant. It will completely be consumed. (0.00392 moles) Ca(OH)2 is in excess. There will react 0.00392 / 2 = 0.00196 moles
There will remain 0.003875 - 0.00196 = 0.001915 moles Ca(OH)2
Step 5: Calculate molarity of Ca(OH)2
Molarity = moles / volume
Molarity Ca(OH)2 = 0.001915 moles / (0.060 L)
Molarity Ca(OH)2 = 0.0319 M
For 1 mol Ca(OH)2 we have 2 moles OH-
Molarity of OH- = 2*0.0319 = 0.0638 M
Step 6: Calculate pH
Since Ca(OH)2 is a strong base
The ph will be the pH of a strong base
pOH = -log[0.0638)
pOH = 1.20
pH = 14 -1.20 = 12.80
what is the mass in grams of 0.375 mol if the element potassium, k?
Answer: 14.625g
Explanation:
No of moles= mass given/molar mass
No of moles given= 0.375mol
Mass is the unknown (?)
Molar mass of K= 39
No of moles = mass given/molar mass
Substitute the values
0.375= mass/39
Cross multiply
Mass = 39×0.375
Mass= 14.625g
The mass is 14.625g
Answer:
14.625g
Explanation:
Mass of a substance =number of moles of the substance × molar mass of the substance
Substance of interest is potassium, K
Given, Number of moles of K =0.375mol
Molar mass of K =39g/mol
Therefore, mass of K =0.375×39=14.625g