Answer : Option A) Atomic number of Arsenic is 33.
Explanation : Arsenic contains same number of protons in its atomic nucleus. In arsenic there are 33 protons found in the atomic nucleus. Hence, the atomic number will be 33. It has 5 valence electrons in its outermost shell, which is also called as valence shell. So, its valency becomes 5.
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Mass CoCl2 = 10.27 g
moles CoCl2 = 10.27 g/ 129.839 g/mol=0.07910
mass water = 17.40 - 10.27=7.13 g
moles water = 7.13 / 18.02 g/mol=0.396
0.396/ 0.07910=5
CoCl2 * 5 H2O
moles CaF2 = 85.8 g/ 78.0748 g/mol=1.10
moles Ca = 1.10
mass Ca = 1.10 x 40.078 g/mol=44.1 g
V = 44.1 / 1.55 =28.5 mL
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Shield volcanos are the tallest. The tallest one is Mauna Loa in Hawaii
Answer:

Explanation:
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In this case, since the chemical reaction between copper and nitric acid is:

By starting with 0.80 g of copper metal (molar mass = 63.54 g/mol) and considering the 1:1 mole ratio between copper and copper (II) nitrate (molar mass = 187.56 g/mol) we can compute that mass via stoichiometry as shown below:

However, the real reaction between copper and nitric acid releases nitrogen oxide, yet it does not modify the calculations since the 1:1 mole ratio is still there:

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