First blank -Same
Second blank-Neutral
Explanation:
salt, sugar and coffee :)
The atomic number for Pb is 82
∴ Pb has 82 protons and 206-82 = 14 protons
The actual mass of Pb nuclei is
=(82 × mass of the proton) + (124 × mass of neutron)
=(82× 1.00728) + (124 × 1.008664) amu
= 207.6713 amu
The mass of lead which is given is 205.9744 amu
∴mass defect is
m = 207.6713 - 205.9744 = 1.6969 amu
=1.6969 × 1.66054 × 10⁻²⁷kg
=2.818 × 10⁻²⁷kg
The binding energy is E = mc²
C is the speed of light in vacuum = 2.9979 × 10⁸m/s
∴ E = 2.532 × 10×⁻¹⁰ J/mol
= 2.532 × 10⁻¹⁰ × 6.023 × 10²³ J/mol
= 1.53811 × 10¹⁴ J/mol
Answer:
Age of rock = 722 million years old
Explanation:
Using the formula; <em>fraction remaining = 0.5ⁿ</em>
where n = number of half lives elapsed.
However, from the given values, fraction remaining = 1.000 - 0.0105
fraction remaining = 0.9895
Substituting in the formula to determine the number of half-lives:
0.9895 = 0.5ⁿ
log 0.9895 = n log 0.5
-0.0045842 = -0.30103 n
number of half lives elapsed, n = 0.0152
Therefore age of rock = 0.0152 x 4.75 x 10¹⁰ years = 7.22 x10⁸ years
Age of rock = 722 million years old
Lithium has one available electron in the outer (valence) shell (2s¹).
1s² 2s¹
