I’m not 100% sure but I think it’s C
Answer: The atomic weight of the metal would be 85.47.
Explanation:
Mass of isotope 1 of metal = 84.9118
% abundance of isotope 1 of metal = 72.15% = 
Mass of isotope 2 of metal= 86.9092
% abundance of isotope 2 of metal = 27.85% = 
Formula used for average atomic mass of an element :
![A=\sum[(84.9118)\times \frac{72.15}{100})+(86.9092)\times \frac{27.85}{100}]]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%2884.9118%29%5Ctimes%20%5Cfrac%7B72.15%7D%7B100%7D%29%2B%2886.9092%29%5Ctimes%20%5Cfrac%7B27.85%7D%7B100%7D%5D%5D)
Therefore, the atomic weight of the metal would be 85.47.
Answer:
0.00676 M
Explanation:
A chemist prepares a solution of calcium bromide by weighing out 0.607g of calcium bromide into a 450ml volumetric flask and filling the flask to the mark with water. Calculate the concentration in mol/L of the chemist's calcium bromide solution. Be sure your answer has the correct number of significant digits.
Step 1: Given data
Mass of calcium bromide (solute): 0.607 g
Volume of solution: 450 mL
Step 2: Calculate the moles corresponding to 0.607 g of calcium bromide
The molar mass of CaBr₂ is 199.89 g/mol.
0.607 g × 1 mol/199.89 g = 0.00304 mol
Step 3: Convert the volume of solution to liters
We will use the conversion factor 1 L = 1000 mL.
450 mL × 1 L/1000 mL = 0.450 L
Step 4: Calculate the molar concentration of calcium bromide
The molarity of the solution is:
M = moles of solute / liters of solution
M = 0.00304 mol / 0.450 L
M = 0.00676 M
When we can get the Kinetic energy from this formula KE= 1/2 M V^2
and we can get the potential energy from this formula PE = M g H
we can set that the kinetic energy at the bottom of the fall equals the potential energy at the top so,
KE = PE
1/2 MV^2 = M g H
1/2 V^2 = g H
when V is the velocity, g is an acceleration of gravitational force and H is the height of the fall.
∴ v^2 = 2 * 9.8 * 8 = 156.8
∴ v= √156.8 = 12.5 m/s
