Answer:
0.0738 M
Explanation:
HNO3 +LiOH = LiNO3 + H2O
Number of moles HNO3 = number of moles LiOH
M(HNO3)*V(HNO3) = M(LiOH)*M(LiOH)
M(HNO3)*50.0mL = 0.100M*36.90 mL
M(HNO3) = 0.100*36.90/50.0 M = 0.0738 M
Protons
Explanation: the atomic number is the same as the number of protons
Answer:
CO32−
Explanation:
We have to consider the valencies of the polyatomic ions involved. Recall that it is only a polyatomic ion with a valency of -2 that can form a compound which requires two sodium ions.
When we look closely at the options, we will realize that among all the options, only CO32− has a valency of -2, hence it must be the required answer. In order to be double sure, we put down the ionic reaction equation as follows;
2Na^+(aq) + CO3^2-(aq) ---------> Na2CO3(aq)
Ans: As changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit will <u>increase.</u>
The energy (E) is related to the frequency (ν) by the following equation:
E = hν
where h = planck's constant
The change in energy i between levels is:
ΔΕ = h(Δν) -----(1)
Based on the above equation, as the changes in energy levels increase, the frequency of emitted radiation will also increase.