Let's mix it up

Boron is classified as a nonmetal.

• True.

• False, it is a metal.

• False, it is a metalloid.

What chemical species does this diagram represent?

• An atom of sodium

• The sodium ion Na⁺

• The neon ion Ne^-

• An atom of neon

Tags

NGSS.MS-PS1-1

Use the diagram to deduce the number of neutrons in an atom of chlorine-37.

• 37 neutrons

• 17 neutrons

• 20 neutrons

• 20 protons

Tags

NGSS.MS-PS1-1

The electron configuration 2,8,6 is that of

• calcium.

• silicon.

• sulfur.

• oxygen.

Tags

NGSS.MS-PS1-1

What is the expected reactivity of the element with electron configuration 2,8,8,1?

• It will form a positive ion by losing 1 electron.

• It will form a positive ion by gaining 1 electron.

• It will form a negative ion by losing 1 electron.

• It will form a negative ion by gaining 1 electron.

Tags

NGSS.MS-PS1-1

When calcium and fluorine react together, an ionic compound will form.

• True, it will have the formula CaF.

• True, it will have the formula CaF₂.

• False, it will form a covalent compound of formula CaF₂.

• True, it will have the formula Ca₂F.

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Use the Lewis dot structures showed to predict how many chlorine atoms can bond with one phosphorus atom.

• 7

• 5

• 3

• 1

Tags

NGSS.MS-PS1-1

What is the correct statement?

• Metalloids are good electrical conductors.

• Ionic and covalent compounds are good heat conductors.

• Covalent compounds have relatively high melting point.

• Ionic compounds are usually hard and brittle.

The ionic compound aluminium sulfate has the formula

• Al₂(SO₄)₃

• Al₃(SO₃)₄

• Al₃(SO₄)₂

• Al(SO₄)₃

Tags

NGSS.MS-PS1-1

The formula of the covalent compound silicon tetrafluoride is

• SiF₃

• SF₄

• SiF₄

• SiCl₄

Tags

NGSS.MS-PS1-1