Answer:
3.2043 x 10²³
Explanation:
No. of Mole of lead (Pb) = 0.532 mol
No. of atoms of lead = ?
Solution:
Formula Used to calculate
no. of moles = numbers of particles (ions, molecules, atoms) /Avogadro's number
Avogadro's no. = 6.023 x10²³
So,
The formula could be written as
no. of atoms of lead Pb = no. of moles x 6.023 x10²³
Put the values in above formula
no. of atoms of lead Pb = 0.532 mol x 6.023 x10²³
no. of atoms of lead Pb = 3.2043 x 10²³
so 3.2043 x 10²³ atoms of lead are contained in 0.532 mole.
Answer:
drip drip water splash (gas)
Explanation:
The answer should be B - Nitrogen Dioxide.
Answer:
800 lb of pure solvent , 1700 lb of 20% solution and 500 lb of 10% solution will be mixed to form 3000 lb of 13 % solution .
Explanation:
3000 lb of 13% solution is required .
Total adhesive in weight = 3000 x .13 = 390 lb of adhesive
Available = 500 lb of 10% solution = 50 lb of adhesive
Rest = 390 - 50 = 340 lb required .
rest mass of solution = 3000 - 500 = 2500 lb
mass of adhesive required = 340 lb
Let the mass of 20% required be V
mass of adhesive = .20 V
.20 V = 340
V = 1700
rest of the volume = 2500 - 1700 = 800 lb which will be of pure solvent
So 800 lb of pure solvent , 1700 lb of 20% solution and 500 lb of 10% solution will be mixed to form 3000 lb of 13 % solution .
Atomic mass silicon = 28.085 u
1 mol Si ---------------- 28.085 g
? ------------------------ 245 g
245 x 1 / 28.085 => 8.72 mol
answer A
