Which of the following is not an element?

• Helium

• Nitrogen

• Water

• Sodium

Tags

NGSS.MS-PS1-1

Which of the substances listed in the image are elements?

• I and II, only

• II, III, and IV, only

• III and IV, only

• I. and III, only

Tags

NGSS.MS-PS1-1

Potassium fluoride, KF, is---

• a compound of two elements

• a mixture of two compounds

• a pure atomic substance

• a pure chemical solution

Tags

NGSS.MS-PS1-1

The molecule is--

• an atom composed of oxygen and carbon elements

• an element composed of oxygen and carbon atoms

• a compound composed of oxygen and carbon atoms

• a mixture composed of oxygen and carbon compounds

Tags

NGSS.MS-PS1-1

Which of the following is an element?

• O₂

• HCl

• MgBr

• Cu(SO₄)₃

Tags

NGSS.MS-PS1-1

Carbon Dioxide (CO₂) is a compound with molecules that consist of one carbon atom and two oxygen atoms. Why is carbon dioxide a compound and not an element?

• Carbon dioxide is a gas.

• Carbon dioxide consists of multiple oxygen atoms.

• Carbon dioxide consists of oxygen atoms and carbon atoms.

Tags

NGSS.MS-PS1-1

Which of the following best describes an element?

• Elements are chemicals that are pure substances held together by chemical bonds.

• Elements are mixtures of atoms and molecules in different combinations.

• Elements are chemicals that are pure substances represented by symbols that have at least one capital letter.

• Elements are chemicals that are formed when a temperature change happens or a precipitate forms.

Which of the following is NOT a compound?

• FeO

• CO

• H₂O₂

• Fe

Tags

NGSS.MS-PS1-1

Which of the following is NOT a chemical change?

• Sugar dissolving in water

• fire burning paper

• souring milk

• rusting metal

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

All of the following are chemical changes EXCEPT-

• digesting beef

• rusting metal

• folding paper

• burning wood

Tags

NGSS.MS-PS1-2