Answer:

Explanation:
Here, we wnat to get the most electronegative atom
On the periodic table, electronegativity increases across a period and decrease down the group
The elements listed are in the same group
Boron is the first member of the group
Boron is the most electronegative atom in the group
Answer:
02 is a product
Explanation:
it doesnt take part in chemical reaction so its not reactant.02 doesnt alter rate of chemical reaction so it cannot be catalyst. it is gas it is not solid so it is a product.
Answer:
The answer is sodium which is the element is the most reactive.
a) (NH4)2SO4 --- 1 mole of it contains 2 moles of N, 8 moles of H, 1 mole of S, and 4 moles of O.
MM = (2 moles N x 14.0 g/mole) + (8 moles H x 1.01 g/mole) + (1 mole S x 32.1 g/mole) + (4 moles O x 16.0 g/mole) = 132 g/mole.
6.60 g (NH4)2SO4 x (1 mole (NH4)2SO4 / 132 g (NH4)2SO4) = 0.0500 moles (NH4)2SO4
b) The molar mass for Ca(OH)2 = 74.0 g/mole, calculated like (NH4)2SO4 above.
4.5 kg Ca(OH)2 x (1000 g / 1 kg) x (1 mole Ca(OH)2 / 74.0 g Ca(OH)2) = 60.8 moles Ca(OH)2
The evidence has to be proven to be true