Answer: 99.45 g
Explanation: we have 22.5 g of Platinum in every 1cm3 of Platinum so if we take 4.42 cm3 of Platinum we will have 4.42 × 22.5 g = 99.45 g of Platinum
Answer: 10 electrons
Explanation:
N represents Nitrogen. Nitrogen has an atomic number of 7, this means in ground state it has 7 electrons also.
But N-3, means Nitrogen has gained 3 more electrons. So, we have 10 electrons
Answer:
14.533 grams of solid precipitate of mercury(II) dichromate will form.
Explanation:

Moles of mercury(II) acetate = 
Moles of sodium dichromate = 
According to reaction , 1 mole of sodium dichromate reacts with 1 mole of mercury(II) acetate , then 0.045906 moles of sodium dichromate will recat with :
of mercury(II) acetate
This means that mercury(II) acetate is present in an excess amount and sodium dichromate is present in limiting amount.So, amount of precipitate will depend upon moles of sodium dichromate.
According to reaction , 1 mole of sodium dichromate gives 1 mole of mercury(II) dichromate , then 0.045906 moles of sodium dichromate will give :
of mercury(II) dichromate
Mass of 0.045906 moles of mercury(II) dichromate:
0.045906 mol × 316.59 g/mol = 14.533 g
14.533 grams of solid precipitate of mercury(II) dichromate will form.