Chemical reaction and equation

Question 1

Fomula of Magnesium oxide

Answer 1

2Mg + O2—–2MgO

Question 2

Write a chemical reaction where YELLOW colour precipitate form.

Answer 2

Pb(NO3)2 + 2KI———2KNO3 + PbI2

Question 3

Photosynthesis chemical equation

Answer 3

6CO2(aq) + 12H2O(l)—–C6H12O6(aq) + 6O2(aq) + 6H2O(l)

Question 4

Write a chemical equation in which hydrogen release with pop sound

Answer 4

Zn + H2SO4——-ZnSO4 + H2

Question 5

Write a chemical equation of methanol!

Answer 5

CO(g) + 2H2(g)——–CH3OH(l)
Above the arrow —-340atm

Question 6

Write a chemical equation in which slaked lime is released.
(Or)
Give a example of exothermic reaction which is also a combination reaction.
(Or)
Write a chemical equation where Quicklime added with water gives us slaked lime along with a release of heat.

Answer 6

The chemical equation in words
Calcium oxide + water ——-Calcium hydroxide+ heat

In simple chemical equation
CaO + H2O——-Ca(OH)2 + Heat
CaO —- Quicklime
Ca(OH)2—-Slaked lime

Question 7

Write a chemical equation where Slaked lime react with Carbon dioxide gives us a shiny layered substance also known as limestone and water
(Or)
Write a chemical equation for marble

Answer 7

The chemical equation in words -
Calcium hydroxide+ Carbon dioxide ——-Calcium carbonate + water

In simplest form-
Ca(OH)2 + CO2——CaCO3 + H2O
Slaked lime - Ca(OH)2
Limestone or shiny layered substance - CaCO3

Question 8

Give examples of Combination reaction

Answer 8

Burning of coal
C(s) + O2(g)—–CO2(g)

Fomation of water
2H2(g) + O2(g)—–2H2O(l)

Question 9

Give example of exothermic reaction

Answer 9

Burning of Natural gas / Methane-
CH4(g) + 2O2(g)——CO2(g) + 2H2O

Respiration-
C6H12O6(aq) + 6O2(aq)——6CO2(aq) + 6H2O(l) + energy