4 is correct. Since gases are made of rapidly moving molecules with a relatively high amount of kinetic energy, the molecules have a hard time coming together to form a liquid. You must lower their kinetic energy with a low temperature and force the molecules together with high pressure.
Answer:
Number of moles = 3.82 mol
Explanation:
Given data:
Number of moles of CO₂ = ?
Mass of CO₂ = 168.2 g
Solution:
Number of moles = mass/molar mass
Molar mass of CO₂ = 44 g/mol
By putting values,
Number of moles = 168.2 g/ 44 g/mol
Number of moles = 3.82 mol
Answer:
ΔU° = 56.0 J
Explanation:
Step 1: Given data
- Work done to compress the gas (w): 83.0 J (When work is done on the gas, w is positive).
- Heat given off to the surroundings (q): -27.0 J (When heat is released to the surroundings, q is negative)
Step 2: Calculate the change in the internal energy of the gas (ΔU°)
The internal energy of a gas is the energy contained within it. We can calculate it using the following expression.
ΔU° = q + w
ΔU° = -27.0 J + 83.0 J
ΔU° = 56.0 J
Answer is: A. 1.1 3 1023 NiCl2 formula units.
m(NiCl₂) = 24.6 g; mass of nickel(II) chloride.
M(NiCl₂) = 129.6 g/mol; molar mass of nickel(II) chloride.
n(NiCl₂) = m(NiCl₂) ÷ M(NiCl₂).
n(NiCl₂) = 24.6 g ÷ 129.6 g/mol.
n(NiCl₂) = 0.19 mol; amount of nickel(II) chloride.
Na = 6.022·10²³ 1/mol; Avogadro constant.
N(NiCl₂) = n(NiCl₂) · Na.
N(NiCl₂) = 0.19 mol · 6.022·10²³ 1/mol.
N(NiCl₂) = 1.13·10²³; number of formula units.
