Greetings!
Significant Digits are:
-Non Zero Numbers
-Zeros in between Non Zero Numbers
-Trailing zeros to the right of the decimal point
So when rounding to 4 significant figures, we get:
1023
Hope this helps.
-Benjamin
Answer:
6 valence electrons
Explanation:
The atom you have given is a sulfur atom. It has 6 valence electrons.
Answer:
age = 63.2 years
Explanation:
Given data
Number of years = 31
number of seconds = 1 billion
Age = ?
Solution
First we convert seconds to minutes
minutes = 1000000000 / 60
minutes = 16666666.667
Now convert minutes to hours
hours = 16666666.667 / 60
hours = 277777.778
Now convert hours to days
days = 277777.778 / 24
days = 11574.074
Now convert days to months
months = 11574.074 / 30
months = 385.802
Now convert months to years
years = 385.803 / 12
years = 32.15
Now add these years with given years
age = 31 + 32.15
age = 63.2 years
Answer:
1. 9.57 × 10^-9 moles.
2. 7.38mol
Explanation:
1.) To find the number of moles there are in the number of particles in an atom, we divide the number of particles (nA) by Avagadro's constant (6.02 × 10^23)
Hence, to find the number of moles (n) of Manganese (Mn), we say:
5.76 x 10^15 atoms ÷ 6.02 × 10^23
5.76/6.02 × 10^(15-23)
= 0.957 × 10^-8
= 9.57 × 10^-9 moles.
2.) Mole = mass/molar mass
Molar mass of sodium chloride (NaCl) = 23 + 35.5
= 58.5g/mol
mole = 431.6 g ÷ 58.5g/mol
mole = 7.38mol
