7H - Atoms, Elements and Molecules

What happens in all chemical changes?

• A gas is produced.
• Heat energy is given out.
• Elements change into a compound.
• One or more new substances are formed.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A compound contains:

• only one type of atom.
• only one element.
• only two elements joined together.
• at least two elements joined together.

Tags

NGSS.MS-PS1-1

Which of the following particle diagrams show molecules of a mixture of elements?

• A

• B

• C

• D

Tags

NGSS.MS-PS1-1

The particle diagram above shows:

• an element.

• a compound.

• a mixture of elements.

• a mixture of compounds.

Tags

NGSS.MS-PS1-1

Which of the following lists contains only elements?

• air, iron, iodine, magnesium
• zinc, gold, aluminium, oxygen
• nitrogen, copper, mercury, water
• chlorine, argon, sodium, limestone

The correct way to write the chemical symbol for the element calcium is:

• ca
• CA
• Ca
• cA

Which of these elements is used to build bridges?

• Iron
• Gold
• Oxygen
• Carbon

Tags

NGSS.MS-ETS1-1

We need to recycle some of our metals more because recycled metals …

• have better properties.
• do not corrode as easily.
• produce more carbon dioxide.
• save our limited natural resources.

Which list contains only non-metal elements?

• oxygen, nitrogen, argon, silicon
• chlorine, oxygen, sulfur, iron
• bromine, helium, carbon, air
• gold, silver, platinum, mercury

Which list contains only typical properties of metals?

• good conductor of heat, brittle, low melting point
• poor conductor of heat, strong, high melting point
• good conductor of electricity, strong, high melting point
• poor conductor of electricity, weak, low melting point