Answer: 0.17M
Explanation:
The equation for the reaction is :
2HNO3 + Ba(OH)2 —> Ba(NO3)2 + 2H2O
From the balanced equation, we obtain :
nA = mole of acid = 2
nB = mole of the base = 1
From the question, we obtain:
Va = Vol. Of acid = 0.105L
Ma = conc. Of acid =?
Vb = Vol of base = 35.7 mL = 0.0357L
Mb = conc. of base = 0.25M.
We solve for the conc. of the acid using:
MaVa / Mb Vb = nA / nB
(Ma x 0.105) / (0.25x0.0357) = 2
Cross multiply to express in linear form. We have:
Ma x 0.105 = 0.25 x 0.0357 x 2
Divide both side by 0.105. We have
Ma = (0.25 x 0.0357 x 2) / 0.105
Ma = 0.17M
Therefore the concentration of the acid(HNO3) is 0.17M
Answer:
Na the valency electrons is 1
The ion charge is positive 1
K the valency electrons is 1
The ion charge is positive 1
Explanation:
Mg the valency electron is 2 The ion charge is positive 2
Ca the valency electron is 2 The ion charge is positive 2
Al the valency electron is 3 The ion charge is positive 3
O the valency electron is 2 The ion charge
is negative 2
F the valency electron is 1 The ion charge is negative 1
Cl the valency electron is 1 The ion charge
is negative 1
N the valency electron is 3 The ion charge is negative 3
S the valency electron is 2 The ion charge is
negative 2
Answer:
- <u>Cadmium has larger atomic radius than sulfur.</u>
Explanation:
Down a period, atomic radii decrease from left to right due to the increase in the number of protons and electrons across a period: when a proton is added the pull of the electrons towards the nucleus is larger, so the size of the atom decreases.
Hence, you can compare the elements that belong to a same period and predict that the atom with lower atomic number (number of protons) will haver larger atomic radius. With that:
- Oxygen and fluorine are in the period 3, being oxygen to the left of fluorine, so oxygen is larger than fluorine.
- Sulfur and chlorine are in the period 4, being sulfur to the left of chlorine, so sulfur is larger than chlorine.
Now see whan happens down a group. Atomic radius increases from top to bottom within a group due to electron shielding. That permits you to compare the size of the elements in a group:
- Fluorine and chlorine are in the same group (17), with chlorine directly below fluorine, so the atomic radius of chlorine is larger than the atomic radius of fluorine.
- Sulfur and oxygen are in the same group (16), with sulfur directlly below oxygen, so sulfur the atomic radius of sulfur is larger than the atocmi radius of oxygen.
So far, you can rank the atomic radius of sulfur, chlorine, fluorine, and oxygen, in increasing order as:
- O < F < Cl < S, concluding that O, F, and Cl have smaller atomic radius than S.
Cadmiun, Cd, is to the left and below sulfur, so both electron shielding (down a group) and increase of the number of protons (down a period) lead to predict the cadmium has a larger atomic radius than sulfur.
C. NO2 is covalent. Hope this helps!
