Answer:
Explanation:
1.
Given parameters:
Number of moles of CaO = 0.22moles
Unknown:
Mass of CaO = ?
Solution:
Mass, number of moles and molar mass are related using the expression below;
Mass = number of moles x molar mass
Molar mass of CaO = 40 + 16 = 56g/mol
Insert the parameters and solve;
Mass = 0.22 x 56 = 12.32g
2
Given parameters:
Number of moles of NaCl = 0.83moles
Unknown:
mass of NaCl = ?
Solution:
Also,
Mass = number of moles x molar mass
Molar mass of NaCl = 23 + 35.5 = 58.5g/mol
Now insert the parameters and solve;
mass = 0.83 x 58.5
mass = 48.6g
3.
Given parameters:
Number of moles of H₂SO₄ = 0.5moles
Unknown:
mass of H₂SO₄ = ?
Solution:
Mass = number of moles x molar mass
Molar mass of H₂SO₄ = 2(1) + 32 + 4(16) = 98g/mol
Insert the parameters and solve;
Mass = 0.5 x 98 = 49g
The ball isn't magnetic, therefore, the nail wasn't attracted towards the ball, but rather towards the magnet.
C. They come from energy sources that never run out.
The first man-made element or artificial element which is produced because it is not found naturally in nature is Technicium, in 1937. Technicium has an atomic number of 43 and atomic mass of 98 g/mol.
To get the number of formula units given 0.14 mg NaCl. We convert first the mass to moles by dividing by the molar mass, then multiplying by Avogadro's number. The final answer is 1.44 x 10^18 formula units.
