Answer:
5.9x10²² atoms of Cu are in one naira coin
Explanation:
To solve this question we need to find the mass of Copper. Then, using its molar mass (Cu = 63.546g/mol) we must find the moles of Cu and its atoms using Avogadro's number:
<em>Mass Cu:</em>
7.3g * 86% = 6.278g is the mass of Cu.
<em>Moles Cu:</em>
6.278g * (1mol / 63.546g) = 0.099moles Cu
<em>Atoms Cu:</em>
0.099moles Cu * (6.022x10²³atoms / 1mol) =
<h3>5.9x10²² atoms of Cu are in one naira coin</h3>
Two chromate ions are contained in this compound. The “di” prefix means Two
Mono- one
Di- two
Tri- three
Tetra- four
Penta- five
Hexa-six
Hepta- seven
Octa- eight
Nona- nine
Deca- ten
Answer: 2.4 ml
Solution :
Molar mass of 
= 17 g/mole
Given,: 28% w/w of solution means 28 g of ammonia in 100 g of solution.
Mass of solution = 100 g
Now we have to calculate the volume of solution.
Molarity : It is defined as the number of moles of solute present in one liter of solution.
where,
n = moles of solute 
= volume of solution in liter = 0.11 L
Now put all the given values in the formula of molarity, we get
Using molarity equation:
