Some Basic Concepts of Chemistry · Chemistry · AP EAPCET
MCQ (Single Correct Answer)
Identify the correct statements from the following.
I. Reaction of hydrogen with fluorine occurs even in dark.
II. Manufacture of ammonia by Haber process is an endothermic reaction.
III. HF is electron rich hydride.
A flask contains 98 mg of $\mathrm{H}_2 \mathrm{SO}_4$. If $3.01 \times 10^{20}$ molecules of $\mathrm{H}_2 \mathrm{SO}_4$ are removed from the flask. The number of moles of $\mathrm{H}_2 \mathrm{SO}_4$ remained in flask is
$$ \left(N_A=6.02 \times 10^{23}\right) $$
The mass % of urea solution is 6 . The total weight of the solution is 1000 g . What is its concentration in $\mathrm{mol} \mathrm{L}^{-1}$ ? (Density of water $=1.0 \mathrm{~g} \mathrm{~mL}^{-1}$ )
( $\mathrm{C}=12 \mathrm{u}, \mathrm{N}=14 \mathrm{u}, \mathrm{O}=16 \mathrm{u}, \mathrm{H}=1 \mathrm{u}$ )
$\mathrm{Xe}(g)+2 \mathrm{~F}_2(g) \xrightarrow[7 \text { bar }]{873 \mathrm{~K}} \mathrm{XeF}_4(\mathrm{~s})$
The ratio of $\mathrm{Xe}: \mathrm{F}_2$ required in the above reaction is
The density of nitric acid solution is $1.5 \mathrm{~g} \mathrm{~mL}^{-1}$. Its weight percentage is 68 . What is the approximate concentration (in $\mathrm{mol} \mathrm{L}^{-1}$ ) of nitric acid ?
$$ (\mathrm{N}=14 \mathrm{u} ; \mathrm{O}=16 \mathrm{u} ; \mathrm{H}=1 \mathrm{u}) $$
The concentration of 1 L of $\mathrm{CaCO}_3$ solution is 1000 ppm . What is its concentration in mol $\mathrm{L}^{-1}$ ?
$$ (\mathrm{Ca}=40 \mathrm{u}, \mathrm{O}=16 \mathrm{u}, \mathrm{C}=12 \mathrm{u}) $$
50 g of a substance is dissolved in 1 kg of water at $$+90^{\circ} \mathrm{C}$$. The temperature is reduced to $$+10^{\circ} \mathrm{C}$$. The density is increased from 1.1 to $$1.15 \mathrm{~g} \mathrm{~cc}^{-1}$$. What is the % change of molarity of the solution?
The empirical formula of calgon is
The statement related to law of definite proportions is
What are $$x$$ and $$y$$ in the following reaction?
$$x \mathrm{~Pb}_3 \mathrm{O}_4 \longrightarrow y \mathrm{PbO}+\mathrm{O}_2$$
An alloy of metals X and Y weighs 12 g and contains atoms X and Y in the ratio of 2 : 5. The percentage of metal X in the alloy is 20 by mass. If the atomic mass of X is 40 amu what is the atomic mass of metal Y ?
If 0.2 moles of sulphuric acid is poured into 250 mL of water, calculate the concentration of the solution.
When 20 g of CaCO$$_3$$ is treated with 20 g of HCl, the mass of CO$$_2$$ formed would be