4) fission is a nuclear reaction where the nucleus of a reactant breaks apart
1. Answer;
Copper (ii) carbonate.
The name of the compound CuCO3 is copper (ii) carbonate.
Explanation;
Cu is the chemical symbol for the copper and CO3 is the chemical symbol for the carbonate group and each one of them has valency of two. Therefore, a compound CuCO3 is formed.
2. Answer;
Yes
Ca2+ reacted with Na2S to form CaS and Na+
Explanation:
Calcium ions reacts with sodium sulfide to form calcium sulfide and sodium ions.
For example; a salt of calcium, calcium carbonate reacts with sodium sulfide to form sodium carbonate and calcium sulfide.
3. Answer;
NaCl and Ag+ do not form a product
Explanation;
The reaction between sodium chloride and silver metal will not take place. This is because silver (Ag) is less reactive than sodium metal and therefore cannot displace sodium from its salt. In other words, silver metal is lower in the reactivity series as compared to sodium metal which indicates sodium metal is more reactive than silver.
4. Answer;
Formation of a white precipitate ; this indicates that silver sulfide is insoluble in water.
Explanation;
When an aqueous solution containing Ag+ ions is added to aqueous solution of sodium sulfide (Na2S), there will be formation of white precipitate. Formation of white precipitate indicates that a reaction has taken place to form a water insoluble compound. The water insoluble compound occurs as a precipitate. The white precipitate is silver sulfide (Ag2S)
2 Ag+ (aq) + Na2S(aq) ----- Ag2S (s) + 2 Na+ (aq)
Q is unlike K value it describes the reaction that is not at equilibrium.
by considering this reaction:
aA+ bB⇄ cC
and our reaction is:
Br2 + Cl2 ⇄ 2 BrCl
According to Q low:
Q= concentration of products/concentration of reactants
but this equation in the gaseous or aqueous states only.
∴ Q = [BrCl]^2 / [Br2] [Cl2]
and we have [Br2] = 0.00366 m [Cl2]= 0.000672 m [BrCl] = 0.00415 m
by substitution:
= [0.00415]^2 / ( [0.00366] * [0.000672])
∴ Q = 7
1) chromium(III) nitrate is acidic, because it is the salt of weak base (chromium(III) hydroxide Cr(OH)₃) and strong acid (nitric acid HNO₃).
2) sodium hydrosulfide is basic, because it is the salt of strong base (sodium hydroxide MaOH) and weak acid (hydrogen sulfide H₂S).
3) zinc acetate is little basic, because zinc hydroxide (Zn(OH)₂) is stronger base than acetic acid (CH₃COOH).
Mixing of pure orbitals having nearly equal energy to form equal number of completely new orbitals is said to be hybridization.
For the compound, 
the electronic configuration of the atoms, carbon and hydrogen are:
Carbon (atomic number=6): In ground state= 
In excited state: 
Hydrogen (atomic number=1): 
All the bonds in the compound is single bond(
-bond) that is they are formed by head on collision of the orbitals.
The structure of the compound is shown in the image.
The Carbon-Hydrogen bond is formed by overlapping of s-orbital of hydrogen to p-orbital of carbon.
In order to complete the octet the required number of electrons for carbon is 4 and for hydrogen is 1. So, the electron in of hydrogen will overlap to the 2p^{3}-orbital of carbon.
Thus, the hybridization of Hydrogen is 
-hybridization and the hybridization of Carbon is 
-hybridization.
The hybridization of each atom is shown in the image.
