Mass of Oxygen : 8.0 g
<h3>Further explanation</h3>
Given
1.51 x 10²³ molecules of Oxygen(O₂)
Required
Mass of Oxygen
Solution
1 mol = 6.02 x 10²³ particles(molecules, atoms, ions)
Can be formulated :
N = n x No
n = moles
No = Avogadro's number
Find moles of Oxygen :
n = N/No
n = 1.51 x 10²³ / 6.02 x 10²³
n = 0.251
Mass of Oxygen :
mass = mol x MW O₂
mass = 0.251 x 32 g/mol
mass = 8.032≈ 8.0 g
A) - this is false: atoms are indivisible according to his theory
b) - this is false: just as in the previous point, the reason is that atoms are indivisible according to his theory
c) no, not true
d) - this is true: atoms of the same element are identical according to the theory
The answer is A. More active than lithium -hope this helps.
The rounded three digits for the given number is 2.46
<u>Explanation:</u>
Significant figures are the number of digits in a value which contributes to the degree of accuracy of the value while measuring
<u>Rules:</u>
- Digits which are not zero are always essential.
- Any zeros between two major digits are important.
- Only a final zero or trailing zeros are important in the decimal section
<u>Solution:</u>
- Given number- 2.45986
- Decimals- 5 digits
- Scientific Notation
-2.45986 × 10^0
- Applying the rules until rounding the 3 digits we get,
- The rounded three digits for the given number is 2.46
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