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

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 = \(40 \, \text{g mol}^{-1}\))

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