Explanation:
Percentage composition = 2/18 = 11.11%.
You must first know that the number of protons and neutrons are same, and neutrons number may vary. Carbon 12 has 6 protons, 6 neutrons and 6 electrons. Sodium 23 has 12 protons , 12 electrons and and 11 neutrons. Silver 108 has 47 protons, 47 electrons and 61 electrons. Finally, Sulfur 32 has 16 protons, 16 nuetrons and 16 electrons. Basically the number of neutrons in an atom can be found by subtracting proton number from mass number
Answer:
Gamma ray
Explanation:
Radio waves have low energy photons, microwave photons have a little more energy than the radio waves, infrared photons have more energy than the microwave, then visible, ultraviolet, X-rays, and, the most energetic of all is the gamma-rays
Answer:
8.0 × 10²¹ atoms contain 1.33 × 10⁻² moles.
Explanation:
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,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
Given data:
Number of atoms = 8.0 × 10²¹ atoms
Number of moles = ?
Solution:
One mole of Cu = 6.022 × 10²³ atoms
For 8.0 × 10²¹ atoms:
(1 mol / 6.022 × 10²³ atoms)×8.0 × 10²¹ atoms
1.33 × 10⁻² moles
So, 8.0 × 10²¹ atoms contain 1.33 × 10⁻² moles.
Answer:
212.996 or 213 approx.
hope it helps.
Molar mass of Al - 27
Molar mass of N - 14
Molar mass of O - 16
so, the molar mass of (No3)3 will be (14+16×3)3 which is equals to 186.
so, Molar mass of Al(No3)3 will be 186+27 = 213.