Answer:
. CuO
Explanation:
Since oxygen also has -2 the valency will cancel out the +2 on Cu leaving CuO
Explanation:If the mass of the object stays the same but the volume of the object decreases then its density becomes greater. If the volume of the object stays the same but the mass of the object increases then its density becomes greater.
Water and dimond are the 2 pure substances
I did the test and the answer is C.
<span>To solve this we need to balance the equations first.
So Hg + S --> HgS is balanced
One mole of Hg requires one mole of S to form one mole of HgS.
Number of moles of Sulphur = mass/ molar mass = 157/32 = 4.906
So 4.90 moles of S reacts with 4.90 moles of Hg.
Hence there are 4.90 moles of 4.90 of Hg.
Mass = number of moles * molar mass of Hg
Mass = 4.906 * 200.59 = 982.891g</span>