Answer:
15
Explanation:
Because the ratio of copper in the solution is 15
6 because the number of valence electrons is always the ones-place of any two-digit group number. So an element in group 18 would have 8 valence electrons
Hope this helps!
Answer is: the molar mass of gas is 82.83 g/mol.
m(gas) = 55.50 g; mass of gas.
V(gas) = 15.0 L; volume of gas.
Vm = 22.4 L/mol; molar volume of gas on STP.
n(gas) = V(gas) ÷ Vm.
n(gas) = 15 L ÷ 22.4 L/mol.
n(gas) = 0.67 mol; amount of gas.
M(gas) = m(gas) ÷ n(gas).
M(gas) = 55.5 g ÷ 0.67 mol.
M(gas) = 82.83 g/mol.