Answer:
A. False.
Every substance contains the same number of molecules i.e 6.02x10^23 molecules
B. False.
Mass conc. = number mole x molar Mass
Mass conc. of 1mole of N2 = 1 x 28 = 28g
Mass conc. of 1mol of Ar = 1 x 40 = 40g
The mass of 1mole of Ar is greater than the mass of 1mole of N2
C. False.
Molar Mass of N2 = 2x14 = 28g/mol
Molar Mass of Ar = 40g/mol
The molar mass of Ar is greater than that of N2.
Explanation:
The reaction between N₂ and F₂ gives Nitrogen trifluoride as the product. The balanced equation is;
N₂ + 3F₂ → 2NF₃
The stoichiometric ratio between N₂ and NF₃ is 1 : 2
Hence,
moles of N₂ / moles of F₂ = 1 / 2
moles of N₂ / 25 mol = 0.5
moles of N₂ = 0.5 x 25 mol = 12.5 mol
Hence N₂ moles needed = 12.5 mol
At STP (273 K and 1 atm) 1 mol of gas = 22.4 L
Hence needed N₂ volume = 22.4 L mol⁻¹ x 12.5 mol
= 280 L
Answer:
84.24 g
Explanation:
Given data:
Mass of oxygen = 75 g
Mass of Al required to react = ?
Solution:
Chemical equation:
4Al + 3O₂ → 2Al₂O₃
Number of moles of oxygen:
Number of moles = mass/ molar mass
Number of moles = 75 g/ 32 g/mol
Number of moles = 2.34 mol
Now we will compare the moles of oxygen with Al.
O₂ : Al
3 : 4
2.34 : 4/3×2.34 = 3.12 mol
Mass of Al required:
Mass = number of moles × molar mass
Mass = 3.12 mol × 27 g/mol
Mass = 84.24 g
Answer:
because no chemical change is happening
Explanation:
