Answer: Type of Chemical Reaction: For this reaction we have a combination reaction. Balancing Strategies: When we add zinc to hydrochloric acid we end up with zinc chloride, a salt, and hydrogen gas. This reaction is actually a good way to make hydrogen gas in the lab.
Answer:Divergent boundaries are typified in the oceanic lithosphere by the rifts of the oceanic ridge system, including the Mid-Atlantic Ridge and the East Pacific Rise, and in the continental lithosphere by rift valleys such as the famous East African Great Rift Valley.
Solution us here,
let the rate of diffusion of H2(r1) be x and⁷ the rate of diffusion of gas(r2) be x+x/6=7x/6.
Molar mass of H2 (M1)=2 g
Molar mass of gas(M2)= ?
Now, from the Ghram's law of diffusion of gas,

here, it looks like I have done wrong.
But all of the answers in option are wrong.
Because, rate of diffusion of any gas is inversely proportional to the square root of its malor mass.
And in the question, gas has higher rate of diffusion than hrdrogen. So it should have molar mass less than hydrogen.
Expansion
Explanation:
Expansion is the change is size of a body with increasing temperature and tension.
Bridges are built of iron. Iron thermally expands in the presence of increased temperature during the day. The length of the iron will increase by simple fractions. At night, when temperature drops, the bar returns back to its initial position.
- The allowance for expansion of the metal is made in order to prevent tension within the structure.
- Not doing this will cause the material to break since there is no free space for the bar to change shape.
Learn more:
Expansion in gases brainly.com/question/9979757
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