A.fluoride
Fluoride helps to prevent tooth decay
Answer:
12.5 g of Li are needed in order toproduce 0.60 moles of Li₃N
Explanation:
The reaction is:
6Li(s) + N₂(g) → 2Li₃N(s)
If nitrogen is in excess, the lithium is the limiting reactant.
Ratio is 2:6
2 moles of nitride were produced by 6 moles of Li
Then, 0.6 moles of nitride were produced by (0.6 .6)/ 2 = 1.8 moles of Li
Let's convert the moles to mass → 1.8 mol . 6.94 g/ 1mol = 12.5 g of Li
Answer:
3%
Explanation:
Substract the actual error from the final and multiply by 100
Answer:-
molecules.
Solution:- The grams of tetrabromomethane are given and it asks to calculate the number of molecules.
It is a two step unit conversion problem. In the first step, grams are converted to moles on dividing the grams by molar mass.
In second step, the moles are converted to molecules on multiplying by Avogadro number.
Molar mass of
= 12+4(79.9) = 331.6 g per mol
let's make the set up using dimensional analysis:

=
molecules
So, there will be
molecules in 250 grams of
.
Photosynthesis turns sunlight, water and carbon dioxide into energy and oxygen. Clorophyll is also a result of this process. "Photosynthesis turns carbon dioxide and water into oxygen and carbohydrates, therefore a chemical change happens." (keep what you wrote there) "It is also an endothermic reaction because SOLAR energy needs to be inputted in order for photosynthesis to occur. The energy input is then stored in the bonds of the glucose that were formed in the plant as a result of photosynthesis."