2 One mole of any substance contains: A 6.02 × 10^21 particles B 6.02 × 10^22 particles C 6.02 × 10^23 particles D 6.02 × 10^24 particles
3 Which of the following is essential for writing empirical formula? A Atomic numbers B Percentage composition C Molecular mass D Density
5 How many particles are present in half mole of a substance? A 3.01 × 10^23 B 6.02 × 10^23 C 1.20 × 10^23 D 12.04 × 10^23
6 Bonding between atoms determines: A Atomic number B Color only C Properties of substances D Neutron number
7 Paula is learning about the properties of metals that make them suitable for industrial purposes. She knows that iron is used in construction. What property of iron makes it suitable for this use? A High reactivity B High strength and relatively low cost C Low density D High electrical conductivity
8 David is studying an ionic compound, NaCl. He wants to calculate the formula mass. He knows Na=23 and Cl=35.5. What is the formula mass of NaCl? A 58.5 g/mol B 60.5 g/mol C 55.5 g/mol D 50.0 g/mol
9 Bond polarity depends upon difference in: A Atomic size B Electronegativity C Mass number D Atomic number
11 Uma is calculating the gram atomic mass of sodium. She knows that the atomic mass of Na is 23 amu. What is the gram atomic mass of sodium? A 23 g B 46 g C 11.5 g D 6.022 × 10^23 g
12 A double bond involves sharing of how many electrons? A One pair B Two pairs C Three pairs D Four pairs
13 Emma is studying the structural formula of water. She knows that water has a bent structure. Which of the following is a structural formula for water? A H2O B H-O-H C HO D O-H-H
15 Quinn is calculating the number of atoms in 3 moles of sodium. How many atoms? A 1.806 × 10^24 atoms B 6.022 × 10^23 atoms C 1.204 × 10^24 atoms D 2.408 × 10^24 atoms
16 Sam is writing the formula for potassium chloride. Potassium has a +1 charge and chloride has a -1 charge. What is the formula? A KCl B KCl2 C K2Cl D K2Cl2
18 Which bond involves complete transfer of electrons? A Covalent B Polar covalent C Ionic D Hydrogen
21 Rachel is studying molecular and structural formulas. She knows that the molecular formula gives the actual number of atoms, but not the arrangement. Which formula shows the arrangement of atoms in a molecule? A Empirical formula B Molecular formula C Structural formula D Formula mass
22 Khalid is learning about hydrogen bonding. He understands that it is a special type of dipole-dipole force. Which of the following elements is necessary for hydrogen bonding? A Nitrogen, oxygen, or fluorine B Carbon, hydrogen, or oxygen C Sodium, potassium, or lithium D Chlorine, bromine, or iodine
24 Samir is learning about the properties of diamond. He knows that diamond is the hardest natural substance. Why is diamond so hard? A Because of weak intermolecular forces B Because of strong covalent bonds in a three-dimensional network C Because of metallic bonds D Because of ionic bonds
25 Fatima is studying the types of covalent bonds based on polarity. She understands that a non-polar covalent bond involves equal sharing of electrons. Which of the following pairs forms a non-polar covalent bond? A H-H B H-Cl C O-H D N-H
27 Bongani is studying the uses of different compounds. He learns that sodium chloride is used as table salt. What type of bond is present in sodium chloride? A Covalent bond B Ionic bond C Metallic bond D Hydrogen bond
28 Mohamed is learning about the uses of diamond. He knows that diamond is used in cutting tools. Why is diamond used in cutting tools? A Because it is very soft B Because it is extremely hard C Because it is a good conductor of heat D Because it is chemically reactive
30 Which is also called Lewis structure? A Orbital diagram B Electron dot formula C Molecular formula D Structural formula