CHEMISTRY - NET IONIC EQUATION! URGENT!

bonkysleuth SG

Form the net ionic equation of Nitric acid and magnesium carbonate. The resultant products should be salt, water and CO2 gas.

2HNO3 (aq) + MgCO3 (s) -> H2O +CO2 +Mg(NO3)2

2H+ + 2NO3- + MgCO3 -> H2O +CO2 +Mg2+ + 2NO3-

cancel away 2NO3-

and I'm left with 2H+ +MgCO3 -> H2O + CO2 +Mg2+

second question.

Zince Oxide and HCl. I'm not sure of how to write the chemical formula of zinc oxide because i do not know the charge of zince and the products of the reaction. can someone help??

The 3rd question goes like this.

sulphuric acid and calcium hydroxide.

H2SO4 (aq) + Ca(OH)2 (this should be in solid state, i think) -> 2H2O + CaSO4

2H+ +SO4 2- + Ca(OH)2 -> 2H2O + Ca2+ + SO4 2-

cancel away SO4 2-. and you get the highlighted equation. it seems wrong. but what did i make a mistake?

weewee SG

Q2) ZnO (s) + 2H+ + 2Cl- -> H2O + Zn2+ + 2Cl-

Q1 and Q3 should be right. I am not entirely sure of my answer because i have not touched chemistry for a long time.

^tamago^ SG

2 H⁺ + (CO₃)^2- ⇒ H₂O + CO₂
ZnO + 2 H⁺ ⇒ H₂O + Zn²⁺
2 H⁺ + Ca(OH)₂ ⇒ Ca²⁺ + 2H₂O

bonkysleuth SG

2 H⁺ + (CO₃)^2- ⇒ H₂O + CO₂
ZnO + 2 H⁺ ⇒ H₂O + Zn²⁺
2 H⁺ + Ca(OH)₂ ⇒ Ca²⁺ + 2H₂O

May I know how do you get the charge for zinc? And how do you know what products the reaction will form?

weewee SG

Zinc is a transition metal and transition metal usually have +2 and higher charges. As you read and study more chemistry, you will be more familiar with their charges and all.

Chemistry is essentially about studying all the 100+ elements and also applying them on practicals. Some people can remember all the elements from the periodic table!

16/f/lonely SG

May I know how do you get the charge for zinc? And how do you know what products the reaction will form?

You'll know as your chem level increases. Laughing

Darkness_hacker99 SG

At O level,if the charge for Zn is not stated, then treat it as Zn2+ . standard.

ultranova3 SG

Zinc is a transition metal and transition metal usually have +2 and higher charges. As you read and study more chemistry, you will be more familiar with their charges and all.

Chemistry is essentially about studying all the 100+ elements and also applying them on practicals. Some people can remember all the elements from the periodic table!

Zinc is not a transition metal. It does not qualify to be a transition metal because:

It does not form colored compounds. It forms colourless compounds with complete 3d10 orbitals. As such, there will be no splitting of 3d orbitals. If you want to know more about this, you should read up on "Crystal Field Theory" (or "ligand field theory" but this requires advanced understanding on Molecular Orbitals as you need to construct MO diagrams to understand LFT) which will explain all the orbital splitting in transition metals and their ligand formation.

Zinc has only one oxidation states. While transition metals have multiple oxidation states.

weewee SG

Zinc is not a transition metal. It does not qualify to be a transition metal because:

Zinc has only one oxidation states. While transition metals have multiple oxidation states.

I read up wiki. Zinc is a transition metal. http://en.wikipedia.org/wiki/Transition_metal

Yes it does not form colored compounds and it lacks a lot of chemical properties that most other transition metals have. However, It is not a requirement to need to have these properties to be a transition metal.

I think zinc's physical properties do match other transition metals though. (etc boiling point, density, tensile strength)

ultranova3 SG

I read up wiki. Zinc is a transition metal. http://en.wikipedia.org/wiki/Transition_metal

I think zinc's physical properties do match other transition metals though. (etc boiling point, density, tensile strength)

The second definition (IUPAC definition) excludes Zinc. I don't know if O Level specifies that Zn is a transition metal but most of the chemistry you lear in O level will be scapped out in A level. Some of chemistry you learn in A level will be scapped out in University level (which includes the traditional definition of transition metal).