Answer:
Na₂CO₃•H₂O
Explanation:
After it is heated, the remaining mass is the mass of sodium carbonate.
30.2 g Na₂CO₃
Mass is conserved, so the difference is the mass of the water:
35.4 g − 30.2 g = 5.2 g H₂O
Convert masses to moles:
30.2 g Na₂CO₃ × (1 mol Na₂CO₃ / 106 g Na₂CO₃) = 0.285 mol Na₂CO₃
5.2 g H₂O × (1 mol H₂O / 18.0 g H₂O) = 0.289 mol H₂O
Normalize by dividing by the smallest:
0.285 / 0.285 = 1.00 mol Na₂CO₃
0.289 / 0.285 = 1.01 mol H₂O
The ratio is approximately 1:1. So the formula of the hydrate is Na₂CO₃•H₂O.
Answer:
D
Explanation:
I explained how to do it on your other problem so look there :)
The balanced chemical reaction is:
<span>CuCl2 + 2Na → 2NaCl + Cu
We are given the amount of sodium to be used up in the reaction. This will be the starting point for our calculations.
15 g Na ( 1 mol / 22.99 ) ( 1 mol Cul2 / 2 mol Na ) (134.45 g / 1 mol ) = 43.86 g CuCl2 needed to be able to obtain the maximum amount of copper.</span>
It evaporates so the ice cube turns in to water then after words evaporat
It is a nuclear reaction since a change has occurred in the nucleus. In nuclear reactions the particles in the nucleus are changed and one element is transformed into another element when particles in the nucleus gained are lost. Unlike chemical reactions which involve the electrons in an atom, nuclear reaction involve the nucleus. A nuclear reaction may be a nuclear fission or nuclear fusion; An example of nuclear reaction is where two isotopes of hydrogen (tritium and deuterium) are fused together under high pressure and temperature, to form a more stable atom of helium. This is an example of nuclear fusion reaction.
