Solids, liquids and gases all take up volume.
Answer:
Explanation: The lowest pressure in a laboratory is 4.0×10^-11Pa
Using Ideal gas equation
PV = nRT
P= 4.0×10^-11Pa
V= 0.020m^3
T= 20+273= 293k
n=number of moles = m/A
Where m is the number of molecules and A is the Avogradro's number=6.02×10²³/mol
R=8.314J/(mol × K)
PV= m/A(RT)
4.0×10^-11 ×0.020 = m/6.02×10²³(8.314×293)
m = 4.0×10^-11×0.020×6.02×10^23 / (8.314×293)
m = 1.98×10^8 molecules
Therefore,the number of molecules is 1.98×10^8
Answer:
0.83 g
Explanation:
Step 1: Write the balanced equation
Fe + CuSO₄ ⇒ Cu + FeSO₄
Step 2: Calculate the moles corresponding to 0.75 g of Fe
The molar mass of Fe is 55.85 g/mol.
Step 3: Calculate the moles of Cu produced from 0.013 moles of Fe
The molar ratio of Fe to Cu is 1:1. The moles of Cu produced are 1/1 × 0.013 mol = 0.013 mol.
Step 4: Calculate the mass corresponding to 0.013 moles of Cu
The molar mass of Cu is 63.55 g/mol.
Answer: 9.68 x 10^10 grams.
Explanation:
Given that:
Mass of CO2 = ?
Number of molecules of CO2 = 2.2x10^9 molecules
Molar mass of CO2 = ? (let unknown value be Z)
For the molar mass of CO2: Atomic mass of Carbon = 12; Oxygen = 16
= 12 + (16 x 2)
= 12 + 32 = 44g/mol
Apply the formula:
Number of molecules = (Mass of CO2 in grams/Molar mass)
2.2x10^9 molecules = Z/44g/mol
Z = 2.2x10^9 molecules x 44g/mol
Z = 9.68 x 10^10g
Thus, the mass of 2.2x10^9 molecules of CO2 is 9.68 x 10^10 grams.
