NEET Chemistry Some Basic Concepts in Chemistry Laws Of Chemical Combinations MCQs

A mixture of $CO$ and $CO_2$ weighing 1.12 g is treated with an excess of red hot $CuO$. The $CO$ is converted to $CO_2$. The total weight of $CO_2$ produced is 1.6 g. What was the weight percentage of $CO$ in the original mixture?

10 g of a metal oxide on strong heating gave 6.4 g of metal. If the formula of the metal oxide is $M_2O_3$, what is the atomic mass of the metal M?

Two elements X and Y combine to form two compounds $XY_2$ and $X_2Y_3$. If 0.05 moles of $XY_2$ weighs 5 g and 0.10 moles of $X_2Y_3$ weighs 20 g, find the atomic masses of X and Y.

Which of the following experiments definitively proved the Law of Conservation of Mass?

A sample of hydrated copper sulfate ($CuSO_4 \cdot xH_2O$) weighs 25 g. Upon heating to drive off all the water, the anhydrous copper sulfate ($CuSO_4$) remaining weighs 16 g. What is the value of 'x' (the number of water molecules of crystallization)?

If two elements A and B combine in different ratios to form two compounds, the masses of B that combine with a fixed mass of A are in a small whole number ratio. This is a statement of:

Which law states that a chemical compound always contains the same elements combined together in the same fixed proportion by mass?

Two different samples of copper(II) oxide were analyzed and found to contain the same percentage of copper by mass. Which law does this illustrate?

Which law explains why 18g of water always decomposes into 2g of hydrogen and 16g of oxygen?

If two elements A and B combine to form two compounds AB and AB2, and 1g of A combines with 0.5g of B in AB, how much of B will combine with 1g of A in AB2 according to the Law of Multiple Proportions?