Answer:
[Ar] 4s²
Explanation:
Ca is the symbol for Calcium. It is the 20th element and it has 20 electrons.
The full electronic configuration for calcium is given as;
1s²2s²2p⁶3s²3p⁶4s²
The condensed electronic configuration is given as;
[Ar] 4s²
Answer:
20 g/mol
Explanation:
We can use <em>Graham’s Law of diffusion</em>:
The rate of diffusion (<em>r</em>) of a gas is inversely proportional to the square root of its molar mass (<em>M</em>).

If you have two gases, the ratio of their rates of diffusion is

Squaring both sides, we get

Solve for <em>M</em>₂:



In the presence of heat, copper (II) hydroxide decomposes in to copper (II) oxide.
Cu(OH)₂ (s) ----> CuO (s) + H₂O (l)
upon decomposition, water is removed from Cu(OH)₂
the amount of Cu(OH)₂ decomposed - 3.67 g
number of moles of Cu(OH)₂ - 3.67 g / 97.5 g/mol = 0.038 mol
stoichiometry of Cu(OH)₂ to CuO is 1:1
therefore number of CuO moles formed are - 0.038 mol
CuO reacts with sulfuric acid to form CuSO₄
CuO + H₂SO₄ ---> CuSO₄ + H₂O
stoichiometry of CuO to H₂SO₄ is 1:1
therefore number of H₂SO₄ moles that should react is 0.038 mol
the molarity of H₂SO₄ is 3M
this means that in 1000 ml - 3 mol of H₂SO₄ present
so if 3 mol are present in 1000 ml
then volume for 0.038 mol = 1000/3 * 0.038
= 12.67 ml
Answer:
1. The graph where x axis and y axis are present is called coordinate.
4. 18
The mass of sulfur in the sample is 0.31g
To calculate mass of sulfur in sample: given that amount galena is 2.34g and mass of lead is 2.03 g as galena contain both lead and sulfur the mass of sulfur = mass of galena- mass of lead , that is, 2.34- 2.03=0.31g.The molecular mass is a algebraic sum of atomic mass of each element in the compound thus the mass of the compound can be obtained by adding atomic of each element. Lead(II) sulphide occurs naturally as the mineral galena, often known as lead glance (PbS). It is a significant source of silver and the most significant lead ore.
To learn more about mass:
brainly.com/question/19694949
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