Answer:Chemistry is important for meeting our needs of food,clothing,shelter,health,energy,and clan air,water,and soil.
If the grade of the ore is 37.3% nickel, then the unknown quantity to get 10 grams of nickel is 0.373 x = 10 grams or x = 10/0.373=26.8 grams or 0.0268 kg needed to dig up to recover the 10 grams of nickel. At this grade of ore, 1 kilogram would yield 373 grams of nickel.
I think the answer is true.
And a water molecule, this is called a dehydration synthesis. when 2 molecule combine, a water molecule leave.