Question

How many total atoms are in 0.170 g of P2O5?

How many moles of Fe2O3 are in 211 g of the compound?

For the given elements, convert the given mole amounts to grams.

How many grams are in 0.0464 moles of sodium?

How many grams are in 0.250 moles of cobalt?

How many grams are in 0.790 moles of selenium?

Calculate the number of atoms in a 5.49 × 103 g sample of lithium.

How many moles of MgS2O3 are in 175 g of the compound?

What is the formula for copper(II) phosphate? Capitalization and punctuation count!

How many atoms of phosphorus are in 2.10 mol of copper(II) phosphate?

Answer 1

m = 0.170g of P_2O_5 n = mass/molar mass = 0.170g/141.944 g/mol = 0.001197 mol 1.197 times 10^-3 mol no of atoms = N_A times n = 1.197 times 10^-3 mol times 6.023 times 10^23 atoms/mol 7.2134 times 10^20 atoms of P_2O_5 Ino.17g Fe_2O_3 mass = 211g [molar mass of Fe_2O_3 = 159.69g/mol] no. of moles of Fe_2O_3(n) = mass /molar mass = 2119/159.69 g/mol therefore n = 1.3213 moles I) n = 0.0464 mol of Na n = mass/molar mass => mass = (n) times (molar mass) [molar mass of N_a = 22.989] Therefore mass = 0.0464 times 22.989(mol times g/mol) 1.0666g II)n = 0.250 mol of cobalt mass = n times molar mass [molar mass of CO = 58.933 g/mol) 0.250 times 58.933 [mol times g/mol] 14.733g III) n = 0.790 mol of selenium mass = n times molar mass [molar mass of Se = 78.96 g/mol] 0.790 times 78.96 mol times g/mol 62.378 grains 5) mg S_2O_3 mass = 175g [molar mass of mg S_2O_3 = 136.433 g/mol]