Answer:
We would need 10 mL of the concentrated CaCl₂ stock solution, and 30 mL of water.
Explanation:
To solve the question asked we can use the C₁V₁=C₂V₂ equation, where:
We <u>solve for V₁</u>:
We would need 10 mL of the concentrated CaCl₂ stock solution, and (40-10) 30 mL of water.
Answer:
3.61 * 10 ²⁴atoms.
Explanation:
Moles is denoted by given mass divided by the molecular mass ,
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
From the question ,
w = 582 g
m = 194 g/mol
The number of moles can be calculated from the above formula , and substituting the respective values ,
n = w / m = 582 g / 194 g/mol = 3 mol
In the molecular formula of caffeine ,
<u>In 1 mole of caffeine their are - 2 moles of Oxygen.
</u>
Therefore , in 3 moles of Caffeine there will be 6 moles of oxygen.
As well know ,
one mole of any substance contains 6.023*10²³ atoms,
Therefore , in 6 mol of oxygen = 6 * 6.023*10²³ atoms = 3.61 * 10 ²⁴atoms.
Answer:
–187.9 J/K
Explanation:
The equation that relates the three quantities is:
where
is the Gibbs free energy
is the change in enthalpy of the reaction
T is the absolute temperature
is the change in entropy
In this reaction we have:
ΔS = –187.9 J/K
ΔH = –198.4 kJ = -198,400 J
T = 297.0 K
So the Gibbs free energy is
However, here we are asked to say what is the entropy of the reaction, which is therefore
ΔS = –187.9 J/K
The answer is A, mass and volume.
The equation for density, <span>ρ,</span> is ρ = m/V. m is mass and V is volume.
