Chemical Equations and chemical reactions

The sum of reactants masses in any chemical reaction is …..the sum of products masses

• doubled
• more than
• equal to
• less than

Tags

NGSS.HS-PS1-7

The bright magnesium ribbon changes into a white powder of …..when it burns in air.

• magnesium nitrite
• magnesium oxide
• magnesium hydroxide
• magnesium dioxide

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

If the molecule of carbon dioxide consists of one atom of carbon and two atoms of oxygen, knowing that the mass of carbon is 12 and that of oxygen is 16, so the mass of two molecules of carbon dioxide equals…..gm

• 22
• 44
• 88
• 33

Tags

NGSS.HS-PS1-7

On applying the law of constant ratios on the following reaction we will find

• a. each 48g (Mg) combines with 32 g (O) to form 80g (MgO)

• b. each 24g (Mg) combines with 16 g (O) to form 40g (MgO)

• c. each 12g (Mg) combines with 8 g (O) to form 20g (MgO)

• d. (a), (b) and (c ) are correct

Tags

NGSS.HS-PS1-7

Direct combination reaction takes place between …….

• two non-metals
• a metal and non-metal
• a compound with another
• all the previous answers

Tags

NGSS.MS-PS1-5

Which of he following is considered a correct and balanced chemical equation?

• 
• 
• 
• 

Tags

NGSS.HS-PS1-7

The……equation verifies the law of conservation of matter

• N₂+H₂-->NH₃

• NO +O₂ --> NO₂

• KCl + AgNO₃ --> AgCl + KNO₃

• H₂O --> H₂ +O₂

Tags

NGSS.HS-PS1-7

Ammonia combines with conc. Hcl producing ………of ammonium chloride

• white ppt.
• brown clouds
• white clouds
• brown ppt.

Increasing the ratio of …gas in the atmosphere leads to increasing the air temperature.

• carbon dioxide
• carbon monoxide
• nitric oxide
• sulpher dioxide

Tags

NGSS.HS-ESS2-4

NGSS.HS-ESS2-6

Chemical reactions are used in …..

• medicines industry
• fertilizers industry
• food industry
• all the previous answers

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5