Answer:
Energy is never lost, it just changes from one form to another
Answer: 37 protons, 48 neutrons, and 36 electrons.
Explanation: I assume "Revision" is Rubidium. It is atomic number 37, so it has 37 protons. It's atomic mass is 85, so it has an average of (85-37) = 48 neutrons. It has a charge of +1, so one electron of the original 37 has left.
Answer:
Empirical SiCl3
Molecular Si2Cl6
Explanation:
Since it contains 79.1% chlorine, this means it contains (100 - 79.1)% silicon = 20.9% chlorine
To get the empirical formula, we firstly need to know the atomic masses of both chlorine and silicon. This is 35.5 and 28
We then divide the percentage abundances by the corresponding atomic masses.
Cl = 79.1/35.5 = 2.23
Si = 20.9/28 = 0.75
We then divide by the smallest, which is 0.75
Cl = 2.23/0.75 = 3
Si = 0.75/0.75 = 1
The empirical formula is thus SiCl3
To get the molecular formula:
(28+3(35.5))n = 269
134.5n = 269
n = 269/134.5 = 2
The molecular formula is Si2Cl6
Answer:
[C] carbon solid
Explanation:
Pure solids and liquids are never included in the equilibrium constant expression because they do not affect the reactant amount at equilibrium in the reaction, thus since your equation has [C] as solid it will not be part of the equlibrium equation.
The conversations need to solve this problem:
1 cal = 4.184 joules
1 Kcal= 1000 calories
1 kj= 1000 joules
or a more direct approach---->> 1 Kcal = 4.184 Kjoules
8.4 kcal (1000 calories/ 1 Kcal) x (4.184 joules/ 1 cal) x (1 Kj/ 1000 joules)= 35.1 Kj
or 8.4 kcal (4.184 Kj/ 1 kcal)= 35.1 Kj (same answer)
