Science Bowl 2025 S1 - MLIS Xi'an - Grade 10 - Round 1

Which type of bond is formed by the transfer of electrons from one atom to another?

• Covalent bond
• Ionic bond
• Metallic bond
• Hydrogen bond

What type of bond is most likely to form between two chlorine atoms?

• Covalent bond
• Ionic bond
• Metallic bond
• Hydrogen bond

Which is true about the elements in the same group of the periodic table?

• They have similar physical properties.
• They have the same number of protons.
• They have similar chemical properties.
• They have the same atomic mass.

Which of the following is a correct about ionic bonding?

• Transfer electrons
• Share electrons
• Get electrons
• Lose electrons

Which of the following occurs in an ionic bond?

• Oppositely charged ions attract.
• Two atoms share two electrons.
• Two atoms share more than two electrons.
• Like-charged ions attract.

What is the atomic number of an element?

• The number of protons in the nucleus
• The number of neutrons in the nucleus
• The total number of protons and neutrons
• The number of electrons in the nucleus

Which compound name is correct for NaCl？

• Sodium chloride
• Sodium chlorate
• Sodium chlorite
• Sodium chloroide

A Lewis diagram is best used for demonstrating:

• Atomic mass
• How large is the nuclear forces
• Electron sharing or transfer
• Number of electron orbit

Which of the following is a chemical change?

• Melting of ice
• Boiling of water
• Rusting of iron
• Dissolving sugar in water

What is the term for a substance undergoing a chemical change?

• compound
• reactant
• product
• catalyst