List of top Chemistry Questions on Laws of Chemical Combinations asked in KEAM

The empirical formula of a metal oxide which has $54\%$ metal (M) and $46\%$ oxygen (O) is (Atomic mass of M = $27$ amu and O = $16$ amu)

The number of molecules of ethane (molar mass $=30$) present in 3 g of pure ethane is

Which of the following has the highest molar mass? \((\text{Atomic masses: N}=14,\ \text{O}=16,\ \text{Ag}=108,\ \text{Pb}=208,\ \text{Na}=23,\ \text{H}=1,\ \text{K}=39)\)

How many moles of methane are required to produce $11\ \text{g}$ $CO_{2(g)}$ after combustion? (Molar mass of $CO_{2}=44\ \text{g mol}^{-1}$)

A solution contains \(9.8 \, \text{g}\) of \(H_2SO_4\). How much NaOH is required to completely neutralize it? (molar mass of NaOH = \(40 \, \text{g mol}^{-1}\))

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

Which one of the following will have the largest number of atoms?

An organic compound contains \(24%\) carbon, \(4%\) hydrogen and remaining chlorine. Its empirical formula is

10 g of MgCO$_3$ decomposes on heating to 0.1 mole CO$_2$ and 4 g MgO. The percent purity of MgCO$_3$ is

The compound Na$_2$CO$_3 \cdot x$H$_2$O has 50 % H$_2$O by mass. The value of $x$ is

When 2.46 g of a hydrated salt (MSO\(_4 \cdot x\)H\(_2\)O) is completely dehydrated, 1.20 g of anhydrous salt is obtained. If molecular weight of anhydrous salt is 120 g mol\(^{-1}\), find x.

If 27 g of water is formed during complete combustion of pure propene (C$_3$H$_6$), the mass of propene burnt is

An organic compound contains 90% carbon and 10% hydrogen by mass. Its empirical formula is

Complete combustion of 0.858 g of compound $ X $ gives 2.63 g of $ C{{O}_{2}} $ and 1.28 g of $ {{H}_{2}}O $ . The lowest molecular weight which $ X $ can have, is: