Answer:
66.7 g
Explanation:
Number of atoms = 2×10²¹
Mass of 2×10²¹ atoms = 0.4 g
Mass of 0.5 moles of that element = ?
Solution:
1 mole contain 6.022×10²³ atoms
2×10²¹ atoms × 1 mol / 6.022×10²³ atoms
0.33×10⁻² mol
0.003 mol
0.003 mole have mass of 0.4 g
0.5 mol have mass 0.5/0.003×0.4 g = 66.7 g
<h3><u>Answer;</u></h3>
3p34s23d7
<h3><u>Explanation</u>;</h3>
- Electrons in an atom are contained in specific energy levels that are different distances from the nucleus.
- Within each energy level is a volume of space where specific electrons are likely to be located, called orbitals. Orbitals are of different shapes, denoted by a letter (s, p, d, f, g).
- S-orbital takes a maximum of two electrons, p-orbital take a maximum of six electrons, d-orbital takes a maximum of 10 electrons, and so fourth.
- The electron filling pattern takes; 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p.........
- Therefore; in this case after 3p3, we then go to 4s, with 2 electrons, then 3d which takes 7 electrons.
<h3>
Answer:</h3>
Ni + Pb(NO₃)₂ → Ni(NO₃)₃ + Pb
<h3>
Explanation:</h3>
We are required to write a balanced equation from the word equation;
- Nickel reacts with lead nitrate (II) to produce nickel(III) nitrate and lead
- The equation will be written by writing the symbols of the reactants and products.
That is;
Ni + Pb(NO₃)₂ → Ni(NO₃)₃ + Pb
We then balance the equation;
- To balance the equation, we put appropriate coefficients on reactants and products, so that the number of atoms of each element is equal on both sides of the equation.
- Thus, the balanced equation will be;
2Ni + 3Pb(NO₃)₂ → 2Ni(NO₃)₃ + 3Pb