Answer:
78.3 × 10²³ atoms of helium are present in 52 g.
Explanation:
Given data:
Mass of He = 52 g
Number of atoms = ?
Solution:
First of all we will calculate the number of moles of He
Number of moles = mass /molar mass
Number of moles = 52 g/ 4 g/mol
Number of moles = 13 mol
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 = 6.022 × 10²³ atoms of helium
13 mol × 6.022 × 10²³ atoms of helium / 1 mole
78.3 × 10²³ atoms of helium
Answer:
0.55 g of Cu can produced by this decomposition
Explanation:
Let's think the reaction of decomposition:
2CuO → 2Cu + O₂
Ratio is 2:2. 2 moles of CuO can decompose into 2 moles of Cu and 1 mol of oxygen.
Let's convert the mass of oxyde to moles → 0.695 g. 1 mol/ 79.55 g =
8.74×10⁻³ moles
8.74×10⁻³ mol of CuO decompose to 8.74×10⁻³ moles of Cu
Let's find out the mass → 8.74×10⁻³ mol . 63.55 g/1mol = 0.55 g
Many, srsly alot. can see in the periodic table. group 1 elements can become ions withs +1 charge while group 12 elements can become ions with -2charge
<h2>Answer:</h2>
Justin Bleeber noticed almost 4 chemical changes while conducting his experiment with a soda can. He noticed chemical changes in cracker burns when it heats the water in a soda can. He observed the chemical change when the waves of the gas are seen coming out on the top of the can. He also observes changes while he uses the flame from Bunsen burner to light a wooden split.
