Well first we can say that B. and D. are out BC they are physical changes we are looking for chemical changes when burning gas, the gas is burning and converting into heat energy AKA FIRE!!!. so the answer is indeed (A. <span>Chemical bonds are broken and others are formed.)
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<span />BTW im not a girl every one ask that. the girls in the pic is my GF
any ways i hope you can learn something new from this. :) <3 have any amazing day
Answer:
HS+Na=>NaS+1/2H2(here HS- acts as an acid)
HS-. + HCl=> H2S(g)+ Cl-(here HS- acts as a base)
Answer:

Explanation:
From the given information, since the molecular mass of the ion M+ is not given;
Let's assume M+ = 58.0423
So, by applying the 13th rule;
we will need to divide the mass by 13, after dividing it;
The quotient n = no. of carbon; &
The addition of the quotient (n) with the remainder r = no. of hydrogen.
So;

So;


From the given information; we have oxygen present, so since the mass of oxygen = 16, we put oxygen in the molecular formula by removing
. Also, since the mass is an even number then Nitrogen is 0.
So, we have:

Answer:
1-Pentene
Explanation:
If we look at all the options listed, we will notice that the rate of reaction of bromine with each one differs significantly.
For 1-pentene, addition of bromine across the double bond is a relatively fast process. It is usually used as a test for unsaturation. Bromine water is easily decolorized by alkenes.
Cyclohexane, heptane are alkanes. They can only react with chlorine in the presence of sunlight. This is a substitution reaction. It does not occur easily. A certain quantum of light is required for the reaction to occur.
For benzene, bromine can only react with it by electrophilic substitution in which the benzene ring is retained. A Lewis acid is often required for the reaction to occur and it doesn't occur easily.