Answer:
Hypochlorous acid - Sodium hypochlorite
Explanation:
A buffer works when pH you want is ± 1 unit of pKa of the buffer. For example, for a buffer with pKa 7, it works between 6 and 8 (7-1 and 7+1).
pKa = -log Ka:
pKa boric acid - Sodium borate: 9.23. As you want a pH of 8.0. This buffer has a pKa too high.
pKa Hypochlorous acid - Sodium hypochlorite: 7.46. With this pKa, this buffer is a great choice to prepare it with a pH = 8.0
pKa Formic acid - Sodium formate: 3.74. This pKa is too low to make a buffer with pH = 8.0
Best choice is:
<h3>Hypochlorous acid - Sodium hypochlorite</h3>
The temp. increase was 8.50 degrees <span>C. (my b)
It requires 4.184J to increase the temp. of a 1g solution by 1 degrees </span><span>C.
Total heat required is 16,143J.
Molar Mass NaOH is 40g/mol
Evolved heat/mol NaOH = 51,045J.</span>
Answer:
If the charge is positive, subtract that number from the atomic number to get the number of electrons. You have more protons.
...
Determining the number of electrons-
a) 28 Si protons = 14, electrons = 14, neutrons = 14
14
b) 197 Au b p = 79, e = 79, n = 118
79
c) 40 Ar c p = 18, e = 18, n = 22
18
d) 64 Cu d p = 29, e = 29, n = 35
29
e) 39 K e p = 19, e = 19, n = 20
19
f) 133 Cs f p = 55, e = 55, n = 78
55
THIS ANSWER HELPS YOU..
Explanation:
Answer:
Elements that have atomic numbers from 20 to 83 are heavy elements, therefore the ratio is different. The ratio is 1.5:1, the reason for this difference is because of the repulsive force between protons: the stronger the repulsion force, the more neutrons are needed to stabilize the nuclei.
Answer:
Mass = 10.1 g
Explanation:
Given data:
Mass of Fe₂O₃ produced = ?
Mass of iron rust = 12.0 g
Solution:
Chemical equation:
4Fe + 3O₂ → 2Fe₂O₃
Number of moles of iron:
Number of moles = mass/ molar mass
Number of moles = 12.0 g/ 55.85 g/mol
Number of moles = 0.215 mol
Now we will compare the moles of iron and Fe₂O₃ .
Fe : Fe₂O₃
4 : 2
0.215 : 2/4×0.125 = 0.063 mol
Mass of Fe₂O₃ :
Mass = number of moles × molar mass
Mass = 0.063 mol × 159.7 g/mol
Mass = 10.1 g