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%
Molar mass = 305.42 g/mol
C = ( 12 x 18 / 305.42 ) x 100 => 70.72 % of C
H = ( 1 x 27 / 305.42 ) x 100 => 8.84 % of H
N = ( 14 x 1 / 305.42 ) x 100 => 4.58 % of N
O = ( 16 x 3 / 305.42) x 100 => 15.71% of O
hope this helps!
Answer:
The correct answer is - Mosquitoes transmit the virus as parasites which feed on the blood of host organisms and inject the virus during feeding.
Explanation:
According to the CDC, the seasonal West Nile virus is caused by the mosquitoes of freshwater transmit this disease to humans and others. These mosquitoes are feed on the birds and pick these viruses.
These viruses stick on mosquitoes and when they feed on the blood of humans they transmit these viruses by injecting viruses into the blood of humans.
Answer:
Explanation:
MW of NaOH = 40 g/mol
MW of KCl = 74.55 g/mp;
250 mL = .25 L
100g NaOH / 40 g = 25 mol
100g KCl/ 74.55g = 1.34 mol
Molarity of NaOH: 25/.25 = 100M
Molarity of KCl: 1.34/.25 = 5.36 M
First, determine the number of moles of gold.
Number of moles = 
Given mass of gold =
Molar mass of gold = 196.97 g/mol
Put the values,
Number of moles of gold = 
=
or
Now, molarity = 
Put the values, volume of ocean =
Molarity = 
= 
Thus, average molar concentration = 