Answer:
0.241 × 10³⁰ molecules
Explanation:
Given data:
Mass of Cr(HCO₃)₃ = 9.273 × 10⁷ g
Number of molecules = ?
Solution:
Number of moles = 9.273 × 10⁷ g/ 235 g/mol
Number of moles = 0.04× 10⁷ mol
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 0.04× 10⁷ moles of Cr(HCO₃)₃:
0.04× 10⁷ moles × 6.022 × 10²³ molecules / 1 mol
0.241 × 10³⁰ molecules
The answer to this questions is letterB
Answer:
1.68L
Explanation:
Step 1:
Data obtained from the question. This includes the following:
Initial Molarity (Mi) = 7M
Initial volume (Vi) 0.6L
Final Molarity (Mf) = 2.5M
Final Volume (Vf) =.?
Step 2:
Determination of the final volume of the solution.
This can be achieved as shown below:
MiVi = MfVf
Divide both side by Mf
Vf = MiVi /Mf
Vf = 7 x 0.6 / 2.5
Vf = 1.68L
Therefore, the new volume of the solution is 1.68L
A) a good hypothesis to be put in question for the experiment would be “Fluorescent light can fade color photographs quicker than direct sunlight can.”
B) the controlled variables, or things that will need to be kept constant throughout the experiment, would be the amount of light on each picture, the amount of ink on each picture, the type of ink on each picture, the size of each picture, and the time of day of the light for each picture.
