Answer:
Mass of sodium chloride decomposed = 24.54 g
Explanation:
Given data:
Mass of sodium chloride decomposed = ?
Mass of chlorine gas formed = 15 g
Solution:
Chemical equation:
2NaCl → 2Na + Cl₂
Number of moles of Cl₂:
Number of moles = mass/molar mass
Number of moles = 15 g/ 71 g/mol
Number of moles = 0.21 mol
Now we will compare the moles of Cl₂ with NaCl from balance chemical equation.
Cl₂ : NaCl
1 : 2
0.21 : 2×0.21 = 0.42 mol
Mass of Sodium chloride decompose:
Mass = number of moles × molar mass
Mass = 0.42 mol × 58.44 g/mol
Mass = 24.54 g
The First 2 statements stated above were false whereas the third one is a true statement.
Explanation:
- The viscosity of bitumen is about 100 times greater than the viscosity of water - False
Reason - The viscosity of bitumen is about not 100 times greater than the viscosity of water, it is actually 100, 000 times greater.
- Oil from oil sand deposits is only obtained by first heating the sands at high temperatures is False.
Reason- Oil from oil sand deposits is not obtained by first heating the sands at high temperatures but by using steams
- Oil sands contain sand, water, and light crude oil is true.
Answer:
Explanation:
Firstly, it should be noted that atomic number (number of protons) determines element. And the element with the atomic number 10 (10 protons) is Neon. Hence, Neon-10 (₁₀Ne) is the answer.
Note that sodium has an atomic number of 11. Also, number of protons is usually equal to the number of electrons in neutral atoms, this is because the total number of positive particles (protons) must be equal to the total number of negative particles (electrons) to give a neutral atom.
Nonmetals form negatively charged ions, or anions. They do this because they need to gain one to three electrons in order to achieve an octet of valence electrons, making them isoelectronic with the noble gas at the end of the period to which they belong.
Answer:
20619.4793 years
Explanation:
The half life of carbon-14 = 5730 years
The formula for the half life for a first order kinetic reaction is:
Where,
is the half life
k is the rate constant.
Thus rate constant is:
5730 years=ln(2)/k
k = 1.21×10⁻⁴ years ⁻¹
Using integrated rate law as:
Where,
is the concentration at time t
is the initial concentration
Given that the final concentration contains 8.25 % of the original quantity which means that:
So,
ln(.0825)= -1.21×10⁻⁴×t
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t = 20619.4793 years</u>
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