Answer:
B. To change from a liquid state to a solid state is called Freezing
The complete question is found on the image attached.
Answer:
a) Rb= +1, Br= -1
b)Bromide and rubidium ions are related to krypton
c) C
Explanation:
Rubidium is found in group 1 with a charge of +1. Bromine is found in group 17 with a charge of -1. Both species have the same configuration as krypton. The ionic sizes of the ions are a very similar to each other Rb+ is 166 while Be is 167.
This RbBr is an ionic compound.
<span>69.3 g
First, determine the molar masses involved:
Atomic weight iron = 55.845
Atomic weight carbon = 12.0107
Atomic weight oxygen = 15.999
Molar mass Fe2O3 = 2 * 55.845 + 3 * 15.999 = 159.687 g/mol
Molar mass CO = 12.0107 + 15.999 = 28.0097 g/mol
Determine how many moles of each reactant we have
Moles Fe2O3 = 189 g / 159.687 g/mol = 1.18356535 mol
Moles CO = 63.0 g / 28.0097 g/mol = 2.249220806 mol
For every mole of Fe2O3, we need 3 moles of CO. So let's see how many moles of Fe2O3 is consumed by dividing moles CO by 3.
2.249220806 mol / 3 = 0.749740269 mol
So we'll be consuming 0.749740269 moles of Fe2O3, subtract that from what we started with
1.18356535 mol - 0.749740269 mol = 0.433825081 mol
Now multiply by the molar mass of Fe2O3
0.433825081 mol * 159.687 g/mol = 69.27622574 g
Rounding to 3 significant figures gives 69.3 g</span>
