can you answer all these questionsWhich of the following is an amphoteric species?

a$.H_2{S}_{(aq)}$

c$.S{O}_4^{2-}(aq)$

b$.H_{2}S{O}_{4(aq)}$

d$.HS{O}_4^{-}(aq)$

If $900mL$ of water were added to a $100-mL$ solution of NaOH, the $pH$ would:

a$.$ increase by $10$

b$.$ decrease by $10$

c$.$ increase by $1$

d$.$ decrease by $1$

e$.$ it depends on the original concentration of NaOH

Which of the following pairs of compounds could be used to make a buffer solution?

a$.HN{O}_3$ and $NaN{O}_3$

c$.$ NaOH and $NaH{C}_2{O}_4$

b$.N{H}_3$ and $N{H}_{4}Cl$

d$.H_2(P{O}_4{)}^{-}$and $P{O}_4^{3-}$

Nitrogen dioxide is the cause of photochemical smog, the brownish haze produced by car exhaust that

hangs over many cities. It exists in an equilibrium with dinitrogen tetroxide, which is colourless, as shown

below.

$N_2{O}_{4(g)}{?}_{\text{c}\text{o}\text{l}\text{o}\text{u}\text{r}\text{l}\text{e}\text{s}\text{s}}+$ energy $2^{2}N{O}_{2(g)}^{\text{h}\text{a}\text{r}\text{r}}$

Based on this equilibrium, smog would be worse:

a$.$ at higher air pressures

c$.$ in the summer time

b$.$ when there's less traffic

d$.$ in the winter time

In a study of the equilibrium described above, an environmental chemist finds that, at a certain

temperature, a closed flask contains $2\mathrm{.}00mo\frac{l}{L}$ of $N{O}_{2(g)}$ and $5\mathrm{.}00mo\frac{l}{L}o{f}_2{O}_{4(g)}.$ The numerical value for

the equilibrium constant at this temperature is:

a$.0\mathrm{.}800$

b$.0\mathrm{.}400$

c$.2\mathrm{.}50$

d$.1\mathrm{.}25$

Ice cubes are melting in a covered bottle of water at room temperature. What is true about this system?

a$.$ It represents an equilibrium system, because the room is a constant temperature

b$.$ It does not represent an equilibrium system, because the temperature is not constant

c$.$ It represents an equilibrium system, because melting and freezing are happening at equal rates

d$.$ It does not represent an equilibrium system, because there isn't an equal rate of melting and freezing

A reaction quotient is calculated to be $Q=3\mathrm{.}0{10}^{-4}.$ The equilibrium constant for the same reaction is

$K_{eq}=7\mathrm{.}2{10}^{-4}.$ Which statement is correct?

a$.$ The system is at equilibrium.

b$.$ The concentrations of the products are greater than the concentrations of the reactants.

c$.$ The system will attain equilibrium by moving to the right.

d$.$ The system will attain equilibrium by moving to the left.

For the following equilibrium, what will happen if potassium chlorate is added to the system?

pink

purple$/$blue

a$.$ The solution will become more pink.

b$.$ The solution will become more blue.

c$.$ The $pH$ of the system will increase.

d$.$ There will be no change to the system. please