Explanation:
Moles of KCl in new solution = 0.325dm³ * (2.76mol/dm³) = 0.897mol.
Hence volume needed = 0.897mol / (3.95mol/dm³) = 0.227dm³ or 0.227L.
Answer:
89.7 billion in scientific notation = 8.97 × 1010.
Explanation:
Answer:
E) More neutrons in the nucleus
Explanation:
Isotope -
The atoms which have same number of protons but different number of neutrons.
And since , atomic number = protons number
and , mass number = proton + neutrons .
Hence ,
The atomic number will not change , but the mass number will change .
Hence , the correct option is more neutrons in the nucleus .
Answer:
Mass = 595 × 10⁻⁸ g
Explanation:
Given data:
Number of atoms of uranium = 15.0 × 10¹⁵ atoms
Mass of uranium = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
1 mole of uranium = 6.022 × 10²³ atoms of uranium
1 mole × 15.0 × 10¹⁵ atoms / 6.022 × 10²³ atoms of uranium
2.5 × 10⁻⁸ moles
Mass of uranium:
Mass = number of moles × molar mass
Mass = 2.5 × 10⁻⁸ moles × 238 g/mol
Mass = 595 × 10⁻⁸ g