Answer:
Mass of sodium chloride decomposed = 24.54 g
Explanation:
Given data:
Mass of sodium chloride decomposed = ?
Mass of chlorine gas formed = 15 g
Solution:
Chemical equation:
2NaCl → 2Na + Cl₂
Number of moles of Cl₂:
Number of moles = mass/molar mass
Number of moles = 15 g/ 71 g/mol
Number of moles = 0.21 mol
Now we will compare the moles of Cl₂ with NaCl from balance chemical equation.
Cl₂ : NaCl
1 : 2
0.21 : 2×0.21 = 0.42 mol
Mass of Sodium chloride decompose:
Mass = number of moles × molar mass
Mass = 0.42 mol × 58.44 g/mol
Mass = 24.54 g
Answer:
1) Big Bang Theory
2) we are in a phase of the big bang theory
Explanation:
So for number 1 the answer is the -big bang theory- and number 2 there is a theory that pretty much says that were in a constant cycle. what I mean is theoretically in a couple million years the entire universe will form together again into another dense ball and repeat the process. So basically the universe is still in the "expanding phase" and that's what backs up the theory of the big bang (the fact that were in one of the big bang theory's "phases")
Mass 456
relative mass 82
moles
mass = rm x moles
456/82 = 5.5609756....
Answer: The elements with properties intermediate between those of metals and nonmetals are called semimetals (or metalloids).