Introduction to Fundamental Concepts of Chemistry FSC flashcards are an effective revision tool for students preparing for entry tests such as MDCAT, NUST, and ECAT, as well as FSC board examinations. These flashcards cover core topics including units and measurements, mole concept, stoichiometry, empirical and molecular formulas, and significant figures in a clear and concise format. Provided by PLS Academy and designed according to the latest FSC syllabus and entry test patterns, they help students revise key concepts quickly, improve retention, and strengthen chemistry fundamentals, making them ideal for smart preparation and high-scoring performance in both competitive and board exams.
A compound has an empirical (simple) formula, C2H2O. If the experimental molecular weight is found to be in the range 160–170, the molecular formula of this compound is:
(Atomic weight: C = 12.1, H = 1.008, O = 16).
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What is the mass of 2 dm3 of oxygen at S.T.P?
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Which one is not true about isotopes:
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11.207 dm3 of methane at STP has ________ moles of hydrogen atoms:
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The number of neutrons in H2SO4 are ________:
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X-ray work in 20th century shows that diameter of the atoms are of the order:
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A compound of sodium oxide has 74.2% of sodium and 25.8% of Oxygen. The empirical formula of the compound is?
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In which of the following will water evaporate earlier?
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How many molecules are there in 2.1 moles of CO2:
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Which one is monoisotopic element?
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The number of moles of CO2 which contains 16g of oxygen:
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The percentage of nitrogen in ammonium nitrate is:
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The atomic mass, molecular mass, ionic mass or formula mass of a substance expressed in grams is called:
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A sample of 0.7 moles of metal ‘M’ reacts completely with an excess of fluorine to form 45g of MF2. How many moles of F are present in it?
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Find the mass in grams of 1.69 mol of phosphoric acid:
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Formula mass is considered for ___________ compounds instead of their molecular mass:
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Actual yield is always less than theoretical yield due to:
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It is the fact that 22.414 cm3 of any gas has a different mass but the same number of:
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What is the mass in grams of 1.69 moles of phosphoric acid?
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Isotopes are the atoms of same element having different number of _________:
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Avogadro’s constant is the number of:
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Atomicity is determined by number _________ of present in a molecule:
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Greater the number of moles, _________ will be the number of molecules.
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The total number of neutrons in 5g of H2O are:
1 NA = 6.023 x 10^23
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The number of atoms present in a molecule determines its:
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Which of the following has six isotopes?
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A compound has an empirical formula CH2Cl and molecular formula mass as 99gmol-1, identify the compound:
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_______ is a macromolecule found in blood.
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The equivalent weight of iron in Fe2O3 would be:
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Which of the following contains 1 mole of the stated particles?
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Identify the value of R at STP:
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Which one is the molar volume of a gas at STP?
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Correct representation of elements with atomic number and atomic mass is?
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Which of the following has six isotopes?
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In mass spectrometer, detector or collector measures the:
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During combustion analysis, which one is used for absorbing carbon dioxide?
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Which of the following will react with water?
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The volume occupied by 4.4g of CO2 at STP is?
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Choose the correct option regarding number or particles associated with one mole of a substance:
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Which one is the molar volume of the gas at STP?
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The smallest number of molecules are present in?
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Correct representation of element with atomic number and atomic mass is:
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The calculation of the efficiency of a chemical reaction can be checked by knowing the amount of:
Which of the following is not true for a mole?
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Number of neutrons in 6630Zn is:
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Choose the correct option regarding number of particles associated with one mole of a substance:
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The _____ study of composition of pure substance in 17th century clearly shows that few elements are components of many substances
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The atoms of hemoglobin is heavier than H-atoms:
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2 moles of octane (C8H18) burn with 25 moles of oxygen (O2) and produced ___________ moles of carbon dioxide along with 18 moles of water.
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The volume of 𝐶𝑂2 produced by heating 33.5𝑔 𝐿𝑖2𝐶𝑂3 at room temperature and pressure is (𝑀𝑟 𝐿𝑖2𝐶𝑂3 = 67𝑔/𝑚𝑜𝑙):
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Limiting reactant controls the amount of ___________ ?
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27g of Al will react with how much mass of O2 to produce Al2O3?
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Natural gas in homes burns in excess of oxygen, what is the limiting reactant in this case?
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Isotopes are?
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An atom is composed of electrons, protons, neutrons and _________:
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A mole of a substance contains _____ particles.
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The mass number of an atom is:
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Glucose(C6H12O6) is the most important nutrient in a cell for generating chemical potential energy, what is the mass percent of carbon in 1.5g of sample?
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The unit used to express the relative atomic mass is called?
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Chemical equations do not tell about the ________ because of certain limitations:
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The relative atomic mass of oxygen is 16 amu. What is the mass of 2 moles of oxygen gas?
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The bond formed when two or more atoms complete their electron shells by sharing electrons is called __________:
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What is the mass of 2 dm3 of oxygen at S.T.P?
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Calculate the grams of H2O formed when 8g of CH4 burns in excess of oxygen:
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The mass of 𝑁𝑎𝑂𝐻 needed to prepare 0.2 molal solution in 500𝑔 pure water at 4℃ is:
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The negative ions having group of atoms is/are:
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Which of the following statement about Avogadro’s hypothesis is correct?
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The break down of molecular ions from natural products give important information about?
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11.2L of CO2 at STP corresponds to how many number of moles?
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Many elements have fractional atomic masses. This is because:
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If 9.8g of sulfuric acid is dissolved in excess quantity of water, it will yield _______ moles of hydrogen ion (H+) and _________ moles of sulphate ions (SO42-).
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Molecular ions are produced by passing a high-energy electron beam or an x-ray beam through:
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Different kinds of atoms of the same element are called isotopes having different __________ but same ___________ properties.
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The amount of product according to the balanced chemical equation is called as?
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The efficiency of a chemical reactions can be checked by calculating ________ yield.
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The number of moles of CO2 that contain 8g of oxygen is:
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Indicate the incorrect statement from the following:
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Avogadro’s hypothesis is applicable to _______ only.
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The actual yield is always less than the theoretical yield due to:
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Mass of an atom ranges from?
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If the number of molecules of different gases are the same at S.T.P., the occupied volume will be __________:
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The mass of one mole of electron is:
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If we are given the mass of a substance ,we can calculate the _________ of the other substance with the help of a balanced chemical equation:
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The relative abundance of isotopes of elements are measured by?
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The empirical formula of the compound was found to be 𝐶𝐻2𝑂. If the molar mass of the compound is 150𝑔/𝑚𝑜𝑙. The molecular formula of the compound is:
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Atoms having same mass number but different atomic numbers are called?
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Which of the following have the same number of molecules?
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If 9.8g of sulfuric acid is dissolved in excess quantity of water, it will yield ____ moles of hydrogen ion (H+) and _____ moles of sulphate ions (SO42-):
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What mass of NaOH is present in 0.5 mol of sodium hydroxide?
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Determine the number of moles of O in 10.6g of Na2CO3:
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A sample of 0.7 moles of metal ‘M’ reacts completely with an excess of fluorine to form 45 g of MF2. How many moles of F are present in it?
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In stoichiometry, we follow law of ________ while doing calculations:
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Molecular ions are formed by passing:
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Spectrometry is used when reactants and products absorb _____.
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Mass of one mole of chlorine gas is?
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In the gaseous state, the distance between the molecules is ___________ than their diameters:
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The amount of reactant according to the balanced chemical equation is called as?
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