The atomic number is 9 Ions have the same atomic number since atomic number signifies number of protons not electrons
b) three
this is because all integers are sig figs, and all numbers between integers are sig figs. This makes the 40,5 part of 40,500 significant. Place holder zeroes that are not after a decimal are not significant, so the last two zeroes of the number are not significant.
Answer:
73.4% is the percent yield
Explanation:
2KClO₃ → 2KCl + 3O₂
This is a decomposition reaction, where 2 moles of potassium chlorate decompose to 2 moles of potassium chloride and 3 moles of oxygen.
We determine the moles of salt: 400 g . 1. mol /122.5g= 3.26 moles of KClO₃
In the theoretical yield of the reaction we say:
2 moles of potassium chlorate can produce 3 moles of oxygen
Therefore, 3.26 moles of salt, may produce (3.26 . 3) /2 = 4.89 moles of O₂
The mass of produced oxygen is: 4.89 mol . 32 g /1mol = 156.6g
But, we have produced 115 g. Let's determine the percent yield of reaction
Percent yield = (Produced yield/Theoretical yield) . 100
(115g / 156.6g) . 100 = 73.4 %
Hi! Well the formula of kinetic energy is Ke = 0.5 x M x V^2
0.5 x 0.5 x 10^2
0.25 x 20
5 J (joule)
