Answer:
B 100 cm3
Explanation:
The balanced equation is given as;
2H2(g)+ O2(g) --> 2H2O(g)
From the reaction stochiometry, 2 cm3 of H2 would react with 1 cm3 of O2 to form 2 cm3 of H2O
Before Reaction --> 100cm3 of H2, 25cm3 of O2, 0cm3 of H2O
During Reaction --> 50cm3 of H2, 25cm3 of O2, 50cm3 of H2O
(Oxygen is sed uup in the reaction)
After Reaction --> 50cm3 of H2, 0cm3 of O2, 50cm3 of H2O
Total volume left = Unreacted H2 (50cm3) + 50cm3 of H2O formed
Total Volume left = 50 + 50 = 100cm3
When the molarity = moles / volume
so, we need to get the moles of MgCl2:
when moles = mass / molar mass
so, by substitution:
∴ moles = 0.25g / 95.211g/mol
= 0.0026 moles
∴`the molarity = 0.0026 / 0.05L
= 0.052 M
Water is another example of a chemical compound<span>. The two or more component elements of a </span>compound<span> can be separated through chemical reactions. </span>Chemical compounds<span> have a unique and defined structure, which consists of a fixed ratio of </span>atoms<span> held together in a defined spatial arrangement by chemical bonds.
</span>B.<span>compound </span>
Mg (s) ---> Mg²⁺ (aq) + 2e
Co²⁺ (aq) + 2e ---> Co(s)
Cu (s) ---> Cu²⁺ (aq) + 2e
Au²⁺ (aq) + 2e ---> Au(s)
The answer is 9.
First convert 40 cm into metres.
40cm/100= 0.4 metres
0.4 times 9 = 3.6