Answer: > > >
Explanation:
Isoelectronic specie are defined as the molecules which have the same number of electrons.
Atomic number of calcium is 20 and thus has 20 electrons. is formed by loss of 2 electrons and thus has 18 electrons.
Atomic number of potassium is 19 and thus has 19 electrons. is formed by loss of 1 electron and thus has 18 electrons.
Atomic number of chlorine is 17 and thus has 17 electrons. is formed by gain of 1 electron and thus has 18 electrons.
Atomic number of phosphorous is 15 and thus has 13 electrons. is formed by gain of 3 electrons and thus has 18 electrons.
As the number of electrons are same , the more is the nuclear charge i.e. the number of protons , more will the force of attraction towards the nuclei and thus smaller will be the radii and vice versa.
Thus, order of decreasing ionic radii for the given ions is as follows.
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Answer:
A hypothesis is an idea or explanation that you then test through study and experimentation.
Answer:
irreversible changes
Explanation:
Most chemical changes are permanent and cannot be reversed. That is because a chemical change involves changing the molecular composition which can't be reversed. A common example of a chemical change would be burning wood. The wood burning into ash is changing the molecular composition of the wood transforming it to ash. Now can ash be changed back into wood? No, it is a "irreversible change."
Hope this helps.
Answer is: molarity of sodium hydroxide solution is 1.95 M.
m(NaOH) = 68.4 g.
n(NaOH) = m(NaOH) ÷ M(NaOH).
n(NaOH) = 68.4 g ÷ 40 g/mol.
n(NaOH) = 1.71 mol.
V(NaOH) = 875 mL ÷ 1000 mL/L = 0.875 L.
c(NaOH) = n(NaOH) ÷ V(NaOH).
c(NaOH) = 1.71 mol ÷ 0.875 L.
c(NaOH) = 1.954 mol/L.