Answer:
Mass = 0.6 g
Explanation:
Given data:
Moles of NaOH = 0.015 mol
Mass of NaOH = ?
Solution:
Number of moles = mass/ molar mass
by rearranging this formula,
Mass = number of moles × molar mass
Molar mass of NaOH is 40 g/mol
by putting values,
Mass = 0.015 mol × 40 g/mol
Mass = 0.6 g
<span>You are given the
mass of hydrate which is 10.24g and the mass of anhydrate which is 8.74g. Hydrate
means that it contains water and anhydrate means the substance has lost water
during the process. So you just subtract them, 10.24g – 8.74g = 1.5g of water
is lost. Percent hydration is equal to one subtracted to the mass of anhydrate
divided by the mass of hydrate multiplied by 100. So we have, [1-(8.74g/10.24g)]
*100 = 14.65% or 15%. Your answers are correct.</span>
Answer is: a) ionization energy and electronegativity.
1) The ionization energy (Ei) is the minimum amount of energy required to remove the valence electron, when element lose electrons, oxidation number of element grows (oxidation process).
Barium, potassium and arsenic are metals (easily lost valence electrons), chlorine is nonmetal (easily gain electrons).
Alkaline metals (far left in Periodic table) have lowest ionizations energy and easy remove valence electrons (one electron), earth alkaline metals (next right to alkaline metals) have higher ionization energy than alkaline metals, because they have two valence electrons.
Nonmetals are far right in the main group and they have highest ionization energy, because they have many valence electrons.
2) Electronegativity (χ) is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.
Atoms with higher electronegativity attracts more electrons towards it, electrons are closer to that atom.
Nonmetals hava higher electronegativity than metals and metalloids.
3) The atomic radius decreases across the periods because an increasing number of protons, because greater attraction between the protons and electrons.
Answer:
Hello, Your answer is <em>B) Making observations</em>
<u><em>(Hope That Helps Your Answer)</em></u>