They start with the numbers u need to know in order to slove the problem and there has to be a story behind it
1.) homogeneous mixtures
2.) <span>NaCI, because sodium is a metal and chlorine is a nonmetal</span>
3.) I'm thinking the first the option
Answer:
There are 6.022 × 10 23 O atoms in a mole of O atoms. There are 6.022 × 10 23 O 2 molecules in a mole of . Since you have 2 oxygen atoms in one molecule, there are 2 × 6.022 × 10 23 O atoms in a mole of . A 'mole' is not short for a 'molecule
Explanation:
This is an oxidation reduction reaction
oxidation happens when the species gives out electrons.Oxidation state of the element Cu increases from 0 to +2
Cu ---> Cu²⁺ +2e --1)
Reduction happens when the species gains electrons.
Oxidation state of N reduces from +5 to +2
4H⁺ + NO₃⁻ + 3e ---> NO + 2H₂O --2)
To balance the reactions, number of electrons need to be balanced.
Multiply 1st reaction by 3
Multiply 2nd reaction by 2
3Cu ---> 3Cu²⁺ + 6e
8H⁺ + 2NO₃⁻ + 6e ---> 2NO + 4H₂O
add the 2 equations
3Cu + 8H⁺ + 2NO₃⁻ --> 3Cu²⁺ + 2NO + 4H₂O
add 6NO₃⁻ ions to each side
3Cu + 8HNO₃ --> 3Cu(NO₃)₂ + 2NO + 4H₂O
the balanced redox reaction equation is as follows;
3Cu(s) + 8HNO₃(aq) --> 3Cu(NO₃)₂ (aq)+ 2NO(g) + 4H₂O(l)