Answer:
Sc (Scandium) has the given electronic configuration.
Explanation:
The given electronic configuration is [Ar]
.
The last electron enters the d-subshell and hence is a d-block element known as Scandium with chemical symbol Sc.
For 4s subshell
n=4,l=0 and m ranges from -l to +l so m=0.
For 3d subshell
n=3,l=2 and m ranges from -l to +l so m can take values -2,-1,0,+1,+2
Note:
l values for subshells:
s : 0
p : 1
d : 2
f : 3 and so on.
Answer:
C. Mutations are a change in DNA or a chromosome and can be helpful, harmful or may have no affect.
Explanation:
- Mutations are spontaneous random changes that occurs in the genetic make up of an organisms. Mutations are rare and their rate of occurrence is random.
- Mutations may occur on the gene level known as gene mutations or at chromosome levels called chromosomal mutations.
- Mutations may be beneficial, harmful or have no effect on a given organisms. Harmful mutations cause disorders that may lead to abnormality or death of an organisms. Beneficial mutations improve an organisms adaptability to the environment.
Answer:
HA + KOH → KA + H₂O
Explanation:
The unknown solid acid in water can release its proton as this:
HA + H₂O → H₃O⁺ + A⁻
As we have the anion A⁻, when it bonded to the cation K⁺, salt can be generated, so the reaction of HA and KOH must be a neutralization one, where you form water and a salt
HA + KOH → KA + H₂O
It is a neutralization reaction because H⁺ from the acid and OH⁻ from the base can be neutralized as water
Hrxn = Q reaction / mol of reaction
mol of reaction = M * V = 10 * 1 = 10 mmol = 0.01 mol
Q water = m * C * (Tf - Ti)
= (10 + 10) (4.184) (26-20) = 502.08 J
Q reaction = - Q water = -502.08 J
Hrxn = -502.08 / (0.01) = - 50208 J = - 50.21 kJ/mol
Momentum = mass x velocity 750x25 = 18750 kg-m/s.
