Answer:
since there is a decimal point at the end, they are all significant figures so the answer is 5
49 neutrons in each nucleus.
<h3>Explanation</h3>
For each nucleus:
Mass number = Number of protons + Number of neutrons.
The atomic number of a nucleus is the same as its number of protons. The atomic number of the nucleus here is 31. There are 31 protons in each nucleus.
- Mass number = 80;
- Number of protons = Atomic number = 31;
- The number of neutrons is to be found.
Again,
Mass number = Number of protons + Number of neutrons.
80 = 31 + Number of neutrons.
Number of neutrons = 80 - 31 = 49.
Answer:
(a) r = 6.26 * 10⁻⁷cm
(b) r₂ = 6.05 * 10⁻⁷cm
Explanation:
Using the sedimentation coefficient formula;
s = M(1-Vρ) / Nf ; where s is sedimentation coefficient, M is molecular weight, V is specific volume of protein, p is density of the solvent, N is Avogadro number, f if frictional force = 6πnr, n is viscosity of the medium, r is radius of particle
s = M ( 1 - Vρ) / N*6πnr
making r sbjct of formula, r = M (1 - Vρ) / N*6πnrs
Note: S = 10⁻¹³ sec, 1 KDalton = 1 *10³ g/mol, I cP = 0.01 g/cm/s
r = {(3.1 * 10⁵ g/mol)(1 - (0.732 cm³/g)(1 g/cm³)} / { (6.02 * 10²³)(6π)(0.01 g/cm/s)(11.7 * 10⁻¹³ sec)
r = 6.26 * 10⁻⁷cm
b. Using the formula r₂/r₁ = s₁/s₂
s₂ = 0.035 + 1s₁ = 1.035s₁
making r₂ subject of formula; r₂ = (s₁ * r₁) / s₂ = (s₁ * r₁) / 1.035s₁
r₂ = 6.3 * 10⁻⁷cm / 1.035
r₂ = 6.05 * 10⁻⁷cm
<h2>Answer : The thermal energy will flow from the computer to the person.</h2><h3>Explanation :</h3>
Usually computer are such devices which converts electrical energy into thermal energy and then it gets transferred to the person. The energy flows from the higher amount to lower amount. In this case, computer is producing higher thermal energy than the person that's the reason for the flow of energy from computer to the person.
Answer:
A single compound is simultaneously oxidized and reduced.
Explanation:
In chemistry, disproportionation is a simultaneous oxidation and reduction of a single chemical specie.
What this means is that; in a disproportionation reaction, only one compound is both oxidized and reduced. This implies that two products are formed during disproportionation. One is the oxidized product while the other is the reduced product.
Consider the disproportionation of CuCl shown below;
2CuCl -----> CuCl2 + Cu
Here, CuCl2 is the oxidized product while Cu is the reduced product.