Answer: the mass number of the daugther atom is 232,
Explanation:
1) Alpha (α) decay is a nuclear reaction in which a nucleus (parent's nucleus) emits an alpha (α) particle and leads to a different atom (daughter atom).
2) The alpha (α) particle is a nucleus of helium atom, i,e, a nucleus with two protons and two neutrons. The symbol used for the α particles is <em>⁴₂He</em>, where the superscript 4 indicates the mass number (2 protons + 2 neutrons = mass number 4), and the subscript 2 indicates the atomic number (number of protons).
3) Then, to determine the mass number of the daughter atom you just need to do a mass number balance:
mass number of the parent atom = mass number of the daugther atom + mass number of the α particle.
The mass number of the radioactive (parent) atom is 90 protons + 142 neutrons = 232.
∴ 232 = x + 4 ⇒ x = 232 - 4 = 228 ← answer.
The full equation may help you to have a wider vision of the problem:
²³²₉₀ X → ⁴₂ He + ²²⁸₈₈ Y
Note this:
- 232 = 4 + 228 (this is a mass number balance)
- 90 = 2 + 88 (this is an atomic number balance)
- X is the parent atom, and Y is the daughter atom
- You can use a periodic table to determine the identity of the unknown atoms (using the atomic numbers).
Answer:
C4H8O4
Explanation:
To determine the molecular formula, first, let us obtain the empirical formula. This is illustrated below:
From the question given, we obtained the following information:
C = 45.45%
H = 6.12%
O = 48.44%
Divide the above by their molar mass
C = 45.45/12 = 3.7875
H = 6.12/1 = 6.12
O = 48.44/16 = 3.0275
Divide by the smallest
C = 3.7875/3.0275 = 1
H = 6.12/3.0275 = 2
O = 3.0275/3.0275 = 1
The empirical formula is CH2O
The molecular formula is given by [CH2O]n
[CH2O]n = 132.12
[12 + (2x1) + 16]n = 132.12
30n = 132.12
Divide both side by the coefficient of n i.e 30
n = 132.12/30 = 4
The molecular formula is [CH2O]n = [CH2O]4 = C4H8O4
Answer:
pH 9,8 is likely to work best for this separation
Explanation:
Ion exchange chromatography is a chemical process where molecules are separated by affinity to an ion exchange resin. To separate different aminoacids you must use the isoelectric point (That is the pH where the aminoacid will be in its neutral form).
For lysine, PI is:
9,8
For arginine:
10,75
At pH = 9,8 lysine will be in its neutral form and will not be retain in the column but arginine will be in +1 charge being retained by the ion exchange resin.
Thus, <em>pH 9,8 is likely to work best for this separation</em>
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I hope it helps!
D is a scintillation counter.
