Some Basic Concepts In Chemistry Questions

31 Practice QuestionsStart Practicing Now

[Medium]A sample of drinking water was found to contain 0.032 g of fluoride ions dissolved in 16 kg of water. Express the fluoride ion concentration in parts ...
[Medium]In the balanced equation for the reaction of aluminium with dilute sulfuric acid to produce aluminium sulfate and hydrogen gas, what is the stoichiome...
[Easy]How many moles of carbon dioxide are produced when 44 g of carbon dioxide is taken at standard conditions?...
[Medium]A mixture contains 4 mol of nitrogen gas and 1 mol of argon gas. What is the mole fraction of nitrogen in this mixture?...
[Medium]In a reaction where 4 g of hydrogen gas reacts with excess chlorine to form HCl, the actual yield obtained is 128 g. What is the percentage yield of H...
[Medium]According to the Law of Multiple Proportions, if carbon forms two oxides with oxygen where one oxide contains 57.1% oxygen, which of the following is ...
[Medium]A solution is prepared by dissolving 18 g of glucose (\(\text{C}_6\text{H}_{12}\text{O}_6\), molar mass = 180 g/mol) in 500 g of water. What is the mo...
[Medium]When 10.5 g of iron filings are burned completely in excess oxygen, 15.0 g of iron oxide (\(\text{Fe}_2\text{O}_3\)) is formed. What mass of oxygen wa...
[Medium]The average atomic mass of chlorine is 35.5 u. Given that chlorine exists as \(^{35}\text{Cl}\) (atomic mass 35 u) and \(^{37}\text{Cl}\) (atomic mass...
[Medium]In the combustion reaction \(\text{C}_3\text{H}_8 + 5\text{O}_2 \rightarrow 3\text{CO}_2 + 4\text{H}_2\text{O}\), how many moles of oxygen are require...
[Medium]Calculate the number of molecules present in 9 g of water (\(\text{H}_2\text{O}\)). (\(N_A = 6.022 \times 10^{23}\) mol\(^{-1}\), Molar mass of water ...
[Easy]In a reaction between nitrogen and hydrogen gases to form ammonia (\(\text{N}_2 + 3\text{H}_2 \rightarrow 2\text{NH}_3\)), if 2 mol of \(\text{N}_2\) ...
[Easy]What mass of sodium hydroxide (NaOH) must be dissolved in 500 mL of water to prepare a 0.4 M solution? (Molar mass of NaOH = 40 g/mol)...
[Easy]The result of the operation \(3.560 \times 2.5\) rounded to the correct number of significant figures is which of the following?...
[Easy]A hydrocarbon contains 92.3% carbon by mass and has a molar mass of 78 g/mol. What is its molecular formula?...
[Easy]A compound is formed by elements A and B such that two atoms of A combine with three atoms of B. If the atomic mass of A is 20 and that of B is 16, wh...
[Easy]According to the law of multiple proportions, when two elements A and B combine to form more than one compound, the masses of B that combine with a fi...
[Easy]How many molecules are present in 5.6 g of nitrogen gas (N₂)?...
[Easy]Nitrogen and hydrogen react to form ammonia. If 28 g N₂ and 6 g H₂ are mixed, which is the limiting reagent?...
[Medium]10 g of hydrogen reacts with 80 g of oxygen. What is the mass of water formed?...
[Easy]What is the percentage of nitrogen by mass in ammonium nitrate (NH₄NO₃)?...
[Easy]What is the molarity of a solution containing 9.8 g of H₂SO₄ in 500 mL of solution?...
[Medium]A compound contains 40% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. Its empirical formula is:...
[Easy]The number of significant figures in 0.00340 is:...
[Medium]What mass of oxygen is required for complete combustion of 2.2 g of propane (C₃H₈)?...
[Medium]When 10.6 g of Na₂CO₃ reacts completely with excess HCl, what volume of CO₂ gas is produced at STP?...
[Medium]The number of moles of oxygen atoms in 8.8 g of CO₂ is:...
[Easy]Which of the following represents the dimensions of molar mass?...
[Easy]The molality of a solution prepared by dissolving 18 g of glucose (C₆H₁₂O₆) in 100 g of water is:...
[Medium]What is the result of (2.5 × 3.42) / 1.2 when expressed with correct significant figures?...
[Easy]What is the mass of 1.5 moles of calcium carbonate (CaCO₃)?...