Answer: 5
Explanation: add up all the electrons and it will amount to 23. Arranging by the old model for electronic configuration, we have : 2, 8, 8, 5
The last number being 5 represent its valence electron
Answer:
The lanthanides and actinides together are sometimes called the inner transition elements.
Explanation:
They are called this because they come up in the periodic table after actinium
Hope this helps :)
Answer:
We say that the solution is unsaturated.
Explanation:
If the salt solubility is 36 g in 0.1 L of water then we can dissolve 360 g of salt in 1 L of water.
Because the solution contains 200 g of salt in 1 L of water, the solution is unsaturated because more salt can be added until we reach the saturation point.
We call the solution dilute when we compare the concentration of a solution with the concentration of another solution, but here we do not compare different solutions.
Answer:
≅ 16.81 kJ
Explanation:
Given that;
mass of acetone = 31.5 g
molar mass of acetone = 58.08 g/mol
heat of vaporization for acetone = 31.0 kJ/molkJ/mol.
Number of moles = 
Number of moles of acetone = 
Number of moles of acetone = 0.5424 mole
The heat required to vaporize 31.5 g of acetone can be determined by multiplying the number of moles of acetone with the heat of vaporization of acetone;
Hence;
The heat required to vaporize 31.5 g of acetone = 0.5424 mole × 31.0 kJ/mol
The heat required to vaporize 31.5 g of acetone = 16.8144 kJ
≅ 16.81 kJ
The answer is (1) 24. There are 26 protons in nucleus of Fe atom. There is 26 electrons in Fe atom. Fe atom loses 2 electrons and change to Fe2+ ion. So there is 24 electrons in Fe2+ ion.
