Some basic concepts of chemistry practice · Easy

The net charge on ferrous ion is:

Which represents per cent by weight?

An amount of 5 moles of $\text{A,}$ 6 moles of $\text{B}$ and excess amount of $\mathrm{C}$ are mixed to produce a final product $\mathrm{D}$, according to the following reactions.

$\begin{aligned} & \mathrm{A}+2 \mathrm{B} \rightarrow \mathrm{I} \\ & \mathrm{I}+\mathrm{C} \rightarrow \mathrm{B}+\mathrm{D} \end{aligned}$

What is the maximum moles of $\mathrm{D},$ which can be produced assuming that the products formed can also be reused in the reactions?

The volume occupied by one molecule of water (density $1\;g\;\mathrm{c}{\mathrm{m}^-3}$ ) is:

1 mole of methyl amine on reaction with nitrous acid gives at NTP

One mole of a gas is defined as:

Assertion : Equivalent weight of ${Cu}$ in ${CuO}$ is 63.6 and in ${Cu}_2 {O} \,31.8$.

Reason : Equivalent weight of an element $=\frac{\text { Atomic weight of the element }}{\text { Valency of the element }}$

Assertion : A certain element $X$, forms three binary compounds with chlorine containing $59.68 \%, 68.95 \%$ and $74.75 \%$ chlorine respectively. These data illustrate the law of multiple proportions.

Reason : According to law of multiple proportions, the relative amounts of an element combining with some fixed amount of a second element in a series of compounds are the ratios of small whole numbers.

The number of moles of Hydrogen molecules required to produce 20 moles of $N{H_3}$ through Haber’s process

A compound having the empirical formula, $\mathrm{C}_3 \mathrm{H}_4 \mathrm{O}$ has a molecular weight of $170 \pm 5.$ The molecular formula of the compound is

Number of ${Zn}$ atoms present in $122 {~g}$ of ${ZnO}$ is (Atomic wt. of ${Zn}=65$ )

A compound has an empirical formula $\mathrm{C}_2 \mathrm{H}_4 \mathrm{O}$. An independent analysis gave a value of 132.16 for its molecular mass. What is the correct molecular formula?

A sample of hydrogen gas is collected and it is observed that it contains only hydrogen and deuterium atoms in the atomic ratio $6000: 1.$ The number of neutrons in $3.0 \mathrm{~g}$ of such a sample should be nearly

The chloride of a metal contains $52.8 \%$ chlorine by mass. The equivalent weight of metal is

The quantity which changes with temperature is 

What is the percentage of carbon in calcium carbide $(Ca{C_2})$

If ${\mathrm{H}_2}\mathrm{S}{\mathrm{O}_4}$ ionises as ${\mathrm{H}_2}\mathrm{S}{\mathrm{O}_4} + 2{\mathrm{H}_2}\mathrm{O} \to 2{\mathrm{H}_3}{\mathrm{O}^ + } + \mathrm{SO}_4^2$, then total number of ions produced by $\mathrm{0}\mathrm{.1}\;\mathrm{M}\;{\mathrm{H}_2}\mathrm{S}{\mathrm{O}_4}$ will be

The molecular mass of $\mathrm{CaSO}_4 \cdot 2 \mathrm{H}_2 \mathrm{O}$ is

(At. mass of Ca = 40, S = 32)

Dopamine is a neurotransmitter, a molecule that serves to transmit message in the brain. The chemical formula of dopamine is $\mathrm{C}_8 \mathrm{H}_{11} \mathrm{O}_2 \mathrm{~N}.$ How many moles are there in $1 \mathrm{~g}$ of dopamine?