Answer:
2.1mol/L
Explanation:
Number of moles = 0.21 moles
Volume = 0.1L
Molarity of a substance is the number of moles of solute dissolved in a volume of solvent (L)
Molarity = number of moles / volume of solvent
Molarity = 0.21 / 0.1
Molarity = 2.1mol/L
Th correct answer is option C. Calling can be hazardous because it also attracts parasites and predators.
The mating call is used by the males to attract females for sexual reproduction. By using vocal sounds males are not only making themselves attractive to females, they are also making themselves vulnerable to predators.
Thus the mating call can have a disastrous effect on the survival of the species.
Answer: The first isotope has a relative abundance of 79% and last isotope has a relative abundance of 11%
Explanation: Given that the average atomic mass(M) of magnesium
= 24.3050amu
Mass of first isotope (M1) = 23.9850amu
Mass of middle isotope (M2)=24.9858amu
Mass of last isotope(M3)= 25.9826amu
Total abundance = 1
Abundance of middle isotope = 0.10
Let abundance of first and last isotope be x and y respectively.
x+0.10+y =1
x = 0.90-y
M = M1 × % abundance of first isotope + M2 × % of middle isotope +M3 ×% of last isotope
24.03050= 23.985× x + 24.9858 ×0.10 + 25.9826×y
Substitute x= 0.90-y
Then
y = 0.11
Since y=0.11, then
x= 0.90-0.11
x=0.79
Therefore the relative abundance of the first isotope = 11% and the relative abundance of the last isotope = 79%
Ammonia is colorless gas with a characteristic smell. Its density is 0.589 times than air which makes it lighter than air. Ammonia can be easily liquefied due to the hydrogen bonding between the molecules. The boiling point is at -33.3 degrees Celsius and the freezing point is at -77.7 degrees Celsius.
