Chemistry Language Quiz for Grade 7

What is a chemical reaction?

• A process in which substances disappear without any change

• A process in which substances are created out of nothing

• A process in which one or more substances are converted into different substances with different properties.

• A process in which substances remain the same with no change in properties

Explain the difference between a physical change and a chemical change.

• Physical change involves a change in form or appearance, while a chemical change results in the formation of new substances.

• Physical change involves a change in texture, while a chemical change results in a change in density.

• Physical change involves a change in state, while a chemical change results in a change in size.

• Physical change involves a change in color, while a chemical change results in a change in temperature.

What is an atom and what is its structure?

• The basic unit of matter with a nucleus containing protons and neutrons, and electrons orbiting around the nucleus.

• Atoms are made up of only protons and electrons, with no neutrons present in the nucleus.

• The basic unit of matter with a nucleus containing protons and electrons, and neutrons orbiting around the nucleus.

• An atom is a molecule made up of two or more elements bonded together.

Describe the structure of an atom using the terms protons, neutrons, and electrons.

• Neutrons are in the nucleus, while protons and electrons orbit around the nucleus.

• Protons are in the nucleus, while neutrons and electrons orbit around the nucleus.

• Electrons are in the nucleus, while protons and neutrons orbit around the nucleus.

• Protons and neutrons are in the nucleus, while electrons orbit around the nucleus.

What is the periodic table and how is it organized?

• The periodic table is organized by atomic number and recurring chemical properties.

• The periodic table is organized by the number of electrons in each element.

• The periodic table is organized by alphabetical order of elements.

• The periodic table is organized by color and size.

Name the three main categories of elements on the periodic table.

• solids, liquids, gases

• acids, bases, salts

• protons, neutrons, electrons

• metals, nonmetals, and metalloids

What are valence electrons and why are they important in chemical reactions?

• Valence electrons are the neutrons in the outermost shell of an atom. They are important in chemical reactions because they determine the state of matter of an element.

• Valence electrons are the electrons in the outermost shell of an atom. They are important in chemical reactions because they determine the reactivity and bonding behavior of an element.

• Valence electrons are the protons in the outermost shell of an atom. They are important in chemical reactions because they determine the color of an element.

• Valence electrons are the electrons in the innermost shell of an atom. They are important in chemical reactions because they have no effect on reactivity.

Explain the concept of chemical bonding.

• Chemical bonding is the process of changing the properties of compounds.

• Chemical bonding is the process by which atoms are held together to form compounds.

• Chemical bonding is the process of converting compounds into atoms.

• Chemical bonding is the process of separating atoms to form compounds.

What is a chemical equation and how is it written?

• A chemical equation is written using only words to describe the reactants and products

• A chemical equation is written using emojis to represent the reactants and products

• A chemical equation is written using musical notes to represent the reactants and products

• A chemical equation is written using chemical formulas and symbols to represent the reactants and products involved in a chemical reaction.

Balance the chemical equation: H2 + O2 → H2O

• 2H2 + 2O2 → 2H2O2

• H2 + O2 → H2O2

• H2O + O2 → H2O2

• 2H2 + O2 → 2H2O