M = n/V
.5M = n/.100 L
n = .1 L * .5M
n= .05 mols of MgCl2
mass of MgCl2 = .05 mols of MgCl2 * 95.211 grams/ 1 mol of MgCl2
mass of MgCl2 = 4.76 grams
4.76 grams of MgCl2 is needed to make 100 ml of a solution that is .500M, in chloride ion. Bolded = confused
Each orbital must contain a single electron before any orbital contains two electrons.
Answer:
C. Fluorine because the model has 9 protons which is represented by the atomic number
Explanation:
We usually identify an element by the number of protons in them. The number of protons is the atomic number of an atom.
- Every atom has a specific number of protons in them.
- This number of protons is the atomic number.
- According to the periodic law, atoms are arranged on the periodic table based on their atomic number.
- The given fluorine atom has 9 protons which represents the atomic number of the atom.
- This way, the given number clearly shows the right model for identifying the chemical specie.
Water molecules move througout the solute
Answer:
87.5 mi/hr
Explanation:
Because a = Δv / Δt (a = vf - vi/ Δt), we need to find the acceleration first to know the change in velocity so we can determine the final velocity.
vf = 60 mi/hr
vi = 0 mi/hr
Δt = 8 secs
a = vf - vi/ Δt
= 60 mi/hr - 0 mi/hr/ 8 secs
= 60 mi/hr / 8 secs
= 7.5 mi/hr^2
Now that we know the acceleration of the car is 7. 5 mi/hr^2, we can substitute it in the acceleration formula to find the final velocity when the initial velocity is 50 mi/hr after 5 secs.
vi = 50 mi/ hr
Δt = 5 secs
a = 7.5 mi/ hr^2
a = vf - vi/ Δt
7.5 = vf - 50 mi/hr / 5 secs
37.5 = vf - 50
87.5 mi/ hr = vf