2.998e^8 is how I would write it. If you want it with the least amount of decimals, use 3e^8
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%
Answer:
6,8 g
Explanation:
c = 4.18 J/(g * °C) = 4180 J / (kg * °C)
= 25 °C
= 36,4 °C
Q = 325 J
The formula is: Q = c * m * (
)
m = 
Calculating:
m = 325 / 4180 * (36,4 - 25) ≈ 0,0068 kg = 6,8 g
Answer:
Explanation:
depending on the activity series there will probably be a single replacement reaction possibly heat or color change and the copper precipitate out of solution
Answer:
13.7 moles of O₂ are needed
Explanation:
In order to find the moles of reactants that may react to make the products we need to determine the reaction:
Reactants are hydrogen and oxygen
Product: Water
2 moles of hydrogen can react to 1 mol of oxygen and produce 2 moles of water.
Balanced reaction: 2H₂(g) + O₂(g) → 2H₂O(l)
If 2 moles of hydrogen need 1 mol of oxygen to react
Therefore, 27.4 moles of H₂ must need (27.4 .1) / 2 = 13.7 moles of O₂
