Year 9 Chemistry

Which is the best definition for an ion?

• An atom has a net charge greater or less than zero.
• An ion has the same number of electrons as an atom of the same element.
• An ion has a net charge greater or less than zero.
• There is no difference

If an element has 5 protons and 5 electrons, what is its net charge?

• +5
• -5
• 0
• -1

The group of an element tells us...

• The number of protons
• The number of electron shells
• The number of valence electrons
• The number of total electrons

Tags

NGSS.HS-PS1-1

What is the compound formula for Carbon Monoxide?

• CO₂
• CO
• C₂O₄
• None of these

Tags

NGSS.MS-PS1-1

Ionic Bonds are formed between...

• two metals
• two non-metals
• metal and a non-metal
• different every time

H₂SO_{4 (aq)} + KOH _(aq) → K₂SO_{4 (aq)} + H₂O

• Precipitation
• Acid-base
• Combustion
• Single Replacement

The toxicity of a substance refers to ..

• its ability to burn ie catch on fire 
• its ability to react quickly with other substances 
• how its affects your health 
• its ability to explode 

Acids have pH values of

• 7
• less than 7
• more than 7
• 14

The positive particles of an atom are 

• electrons 
• positrons 
• neutrons 
• protons 

the central region of an atom where its neutrons and protons are is its 

• nucleus 
• electron cloud
• core 
• center 

Tags

NGSS.HS-PS1-8