Avogadro's hypothesis states that

Important Questions on Some Basic Concepts of Chemistry

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The number of water molecules is maximum in

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Amongst the following statements, that which was not proposed by Dalton was :

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The amount of sugar $\left({\mathrm{C}}_{12}{\mathrm{H}}_{22}{\mathrm{O}}_{11}\right)$ required to prepare $2\mathrm{L}$ of its $0.1\mathrm{ }\mathrm{M}$ aqueous solution is:

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A sample of a hydrate of barium chloride weighing 61 g was heated until all the water of hydration is removed. The dried sample weighed 52 g. The formula of the hydrated salt is: (atomic mass, Ba = 137 amu, Cl = 35.5 amu)

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Among the following pairs of compounds, the one that does not illustrate the law of multiple proportions, is

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A compound with molecular mass $180$ is acylated with ${\mathrm{CH}}_3\mathrm{COCl}$ to get a compound with molecular mass $390$. The number of amino groups presents per molecule of the former compound is

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In Carius method of estimation of halogens, $250 \mathrm{mg}$ of an organic compound gave $141 \mathrm{mg} \mathrm{AgBr}$. What is the percentage of bromine in the compound (atomic mass of $\mathrm{Ag}=108$ and atomic number of $\mathrm{Br}=80$)?

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The amount of oxygen in $3.6$ moles of water is:

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The statement related to law of definite proportions is

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A bicycle tyre is filled with air having pressure of $270 \mathrm{kPa}$ at $27°\mathrm{C}$. The approximate pressure of the air in the tyre when the temperature increases to $36°\mathrm{C}$ is

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A mixture of gases contains ${\mathrm{H}}_2$ and ${\mathrm{O}}_2$ gases in the ratio of $1:4$ (w/w). What is the molar ratio of the two gases in the mixture?

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$56.0 \mathrm{L}$ of nitrogen gas is mixed with excess of hydrogen gas and it is found that $20 \mathrm{L}$ of ammonia gas is produced, The volume of unused nitrogen gas is found to be_____ $\mathrm{L}$.

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Suppose the elements $\mathrm{X}$ and $\mathrm{Y}$ combine to form two compounds $\mathrm{X}{\mathrm{Y}}_2$ and ${\mathrm{X}}_3{\mathrm{Y}}_2$. When $0.1 \mathrm{mole}$ of $\mathrm{X}{\mathrm{Y}}_2$ weighs $10 \mathrm{g}$ and $0.05 \mathrm{mole}$ of ${\mathrm{X}}_3{\mathrm{Y}}_2$ weighs $9 \mathrm{g}$, the atomic weights of $\mathrm{X}$ and $\mathrm{Y}$ are

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If Avogadro number ${\mathrm{N}}_{\mathrm{A}}$ , is changed from $6.022\times {10}^{23}\mathrm{ }\mathrm{m}\mathrm{o}{\mathrm{l}}^{-1}$ to $6.022\times {10}^{20}\mathrm{ }\mathrm{m}\mathrm{o}{\mathrm{l}}^{-1}$ , this would change:

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An unknown chlorohydrocarbon has 3.55 % of chlorine. If each molecule of the hydrocarbon has one chlorine atom only; chlorine atoms present in 1 g of chlorohydrocarbon are :(Atomic wt. of $\mathrm{Cl}=35.5\mathrm{ }\mathrm{u};$ Avogadro constant $=6.023\times {10}^{23}\mathrm{ }{\mathrm{mol}}^{–1}$)

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The ratio of mass percent of $\mathrm{C} \mathrm{and} \mathrm{H}$ of an organic compound $\left({\mathrm{C}}_{\mathrm{X}}{\mathrm{H}}_{\mathrm{Y}}{\mathrm{O}}_{\mathrm{Z}}\right)$ is $6 : 1.$ If one molecule of the above compound $\left({\mathrm{C}}_{\mathrm{X}}{\mathrm{H}}_{\mathrm{Y}}{\mathrm{O}}_{\mathrm{Z}}\right)$ contains half as much oxygen as required to burn one molecule of compound ${\mathrm{C}}_{\mathrm{X}}{\mathrm{H}}_{\mathrm{Y}}$ completely to ${\mathrm{CO}}_2$ and ${\mathrm{H}}_2\mathrm{O}.$ The empirical formula of the compound ${\mathrm{C}}_{\mathrm{X}}{\mathrm{H}}_{\mathrm{Y}}{\mathrm{O}}_{\mathrm{Z}}$ is

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The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is 1 : 4. The ratio of number of their molecules is:

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Which of the following have same number of significant figures?
(A) $0.00253$
(B) $1.0003$
(C) $15.0$
(D)$163$
Choose the correct answer from the options given below

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By heating $200 \mathrm{g}$ of metal carbonate, $112 \mathrm{g}$ of metal oxide on a gaseous compound are produced. Vapour density of the gaseous compound is $22$. How many moles of gaseous compound is produced in the reaction?

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Which of the following is an example of Law of multiple proportion?