Most Important Basic Concept Quiz Test Online

1) 6Na + Fe₂O₃ → 3Na₂O + 2Fe

If you are provided with 230g Na and 320g Fe₂O₃, then the limiting reactant is:

2) In combustion analysis, which one is used for absorbing carbon dioxide (CO₂)?

3) An acid with molecular mass 104 contains 34.6% C, 3.85% H, and the rest is O. The molecular formula of the acid is:

4) What volume of oxygen is required for the complete combustion of 5 cm³ of C₂H₂?

5) If we know the mass of one substance, we can calculate the volume of another substance and vice versa with the help of a chemical equation. This is called:

6) Which of the following compounds have a empirical formula but no molecular formula?

7) The mass of one mole of chlorine gas is:

8) Mg reacts with HCl as per the following reaction:

Mg (s) + 2HCl (aq) → MgCl₂ (aq) + H₂ (g)

Given that Mg = 21g and HCl = 21g, the excess reactant is:

9) The absorption of CO₂ in KOH solution during combustion analysis is:

10) Which of the following statements  is not true for a mole?

11) How much Al is required to form alumina with 12g of oxygen?

12) Indicate the incorrect statement from the following:

13) When one mole of each of the following is completely burnt in oxygen, which will give the largest mass of CO₂?

14) 11.207 dm³ of methane at STP contains how many moles of hydrogen atoms?

15) The sole products of combustion analysis are:

16) The actual yield is always less than the theoretical yield due to:

17) With the help of the given spectral data, calculate the mass of Neon and choose the best option.

(Percentage of isotopes: ²⁰Ne = 90.92%, ²¹Ne = 0.26%, ²²Ne = 8.82%)

18) Which of the following compounds has the highest percentage of oxygen by weight?

19) How many chlorine atoms are in 2 moles of Cl?

20) The efficiency of a chemical reaction can be checked by knowing the amount of:

1) If we know the mass of one substance, we can calculate the volume of another substance and vice versa with the help of a chemical equation. This is called: (MDCAT 2010)

2) Which of the following has the same number of molecules as present in 11g of CO₂? (MDCAT 2017)

3) One mole of any gas at STP occupies a volume of: (MDCAT 2010)

4) 3.0 moles of calcium will contain how many grams of calcium? (MDCAT 2018)

5) The number of molecules in 9g of ice (H₂O) is: (MDCAT 2014)

6) A researcher prepared a sample of 1-bromopropane from 10g of 1-propanol. After purification, he obtained 12g of product. What is the percentage yield?(MDCAT 2017)

7) Hydrogen burns in chlorine to produce hydrogen chloride. The ratio of masses of reactants in the chemical reaction H₂ + Cl₂ → 2HCl is: (MDCAT 2013)

8) When 8 grams (4 moles) of H₂ react with 2 moles of O₂, how many moles of water will be formed? (MDCAT 2012)

9) The number of moles of CO₂ that contain 8.0g of oxygen is: (MDCAT 2016)

10) The formula which shows the simplest whole number ratio of the atoms of different elements in a compound is called: (MDCAT 2018)

11) An organic compound has an empirical formula of C₃H₃O. If the molar mass of the compound is 110.15 g/mol, what is its molecular formula? (MDCAT 2012)
(Atomic masses: C = 12, H = 1.008, O = 16)

12) An organic sample consisting of carbon, hydrogen, and oxygen was subjected to combustion analysis. 0.5439g of this compound gave 1.039g CO₂ and 0.6369g H₂O. The empirical formula of this compound is: (MDCAT 2016)

13) How many chlorine atoms are in 2 moles of Cl? (MDCAT 2011)

14) Calculate the grams of H₂O formed when 8g of CH₄ burns in excess oxygen. (MDCAT 2017)

15) Determine the number of moles of O in 10.6g of NaCO₂. (MDCAT 2017)

16) Choose the correct option regarding the number of particles associated with one mole of a substance. (MDCAT 2017)

17) A polymer with the simplest formula CH₂ has a molar mass of 28,000 g/mol. Its molecular formula will be: (MDCAT 2014)

18) 10.0 grams of glucose are dissolved in water to make 100 cm³ of solution. Its molarity is: (MDCAT 2015)

19) While finding the relative atomic mass, which of the following standards is used to compare the atomic mass of chlorine (35.5 amu)? (MDCAT 2018)

20) How many moles of sodium are present in 0.1g of sodium? (MDCAT 2015)

1) The average atomic mass of Boron is 10.8. It has two isotopes of masses 10 and 11 respectively. What is the percentage of the isotope with the mass of 10? (MDCAT 2019)

2) Iron is manufactured industrially in a blast furnace using hematite (an ore of iron) and carbon monoxide as a reducing agent.

Fe₂O₃ + 3CO → 2Fe + 3CO₂

Calculate the mass of iron ore used to manufacture 56g of iron with excess carbon monoxide. Assume the process gives 100% yield. (SET 2019)

3) During stoichiometric calculations, which of the following laws must be followed? (MDCAT 2019)

4) The empirical formula of glucose (C₆H₁₂O₆) is: (NMDCAT 2020)

5) Which compound has the highest percentage of nitrogen? (ETEA 2019)

6) The water formed in combustion analysis is usually absorbed by: (ETEA 2016)

7) ​How many moles of calcium carbonate are present in 1.75 kg of calcium carbonate? (MDCAT 2019)
(Ar of Ca = 40, Ar of C = 12, Ar of O = 16)

8) How many oxygen atoms are present in 278g of hydrated ferrous sulfate (FeSO₄·7H₂O = 278amu)? (ETEA 2016)

9) The best standard for the calculation of relative atomic mass is: (NUMS 2019)

10) The efficiency of a chemical reaction can be expressed as: (NMDCAT 2020)

11) According to the law of definite proportions, what is the mass ratio of hydrogen and oxygen in water? (SET 2019)

12) Given the reaction:

2XeF₆+SiO₂→3XeOF₄​+SiF₄​

If 122.6g of XeF₆ reacts with 60g of SiO₂ to form products, identify the limiting reagent and the amount of SiF₄ formed. (XeF₆ = 245.3 amu, SiO₂ = 60 amu, SiF₄ = 104 amu) (ETEA 2016)

13) Which of the following contains more atoms? (ETEA 2019)

14) A mixture of 10 cm³ of oxygen and 50 cm³ of hydrogen is sparged continuously. What is the maximum theoretical decrease in volume? (ETEA 2019)

15) The number of moles of water in 1 kg of ice is: (MDCAT 2019)

16) In a vessel, 10g of N₂, 10g of H₂, and 10g of O₂ are present. Which one will have the least number of atoms? (NMDCAT 2020)

17) Which two elements are isotopes? (MDCAT 2019)

18) A piece of diamond embedded in a gold ring weighs 6.0 grams. How many moles of carbon does it contain? (SET 2019)