Water and oxygen
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Answer:
The answer to your question is given after the questions so I just explain how to get it.
Explanation:
a)
Get the molecular weight of Phosphoric acid
H₃PO₄ = (3 x 1) + (31 x 1) + (16 x 4)
= 3 + 31 + 64
= 98 g
98 g ----------------- 1 mol
0.045 g --------------- x
x = (0.045 x 1) / 98
x = 0.045 / 98
x = 0.00046 moles or 4.6 x 10 ⁻⁴
b)
Molarity = 
Molarity = 
Molarity = 0.0013 or 1.31 x 10⁻³
c)
Formula C₁V₁ = C₂V₂
V₁ = C₂V₂ / C₁
Substitution
V₁ = (0.0013)(1) / 0.01
Simplification and result
V₁ = 0.0013 / 0.1
V₁ = 0.13 l = 130 ml
Because the modern periodic table is according to icnreasing atomic numbers.Ar has the atomic number 18 and potassium 19 so Argron is placed before K in the Modern periodic table.
Number of moles of HCl =

=

= 0.763 mole
From balanced equation:
4 moles of HCl give 2 moles Cl2
0.763 mole HCl give ?? mole Cl2
by cross multiplication :
= 0.38 mole Cl2
mass of Cl2 = moles x molar mass = 0.38 x 70.9 = 27 g
Answer:
A.)
Explanation:
The first structure accurately represents ethyl ethanoate because there is an ethyl group (2 carbons) directly attached to the oxygen within the parent chain and there are 2 carbons (the eth- in ethanoate) attached to the double bonded oxygen.
The second structure is not ethyl ethanoate. There is an ethyl group directly attached to the oxygen within the parent chain. However, there are 3 carbons attached to the double bonded oxygen. This makes the structure ethyl propanoate.