525 grams of tin(II) fluoride are dissolved in water to create a solution with a total
volume of 3.50 L. What is the molarity of the solution?

MOLARITY =  0.9554 mol/dm3

Explanation:

525 grams of SnF2 in 3.50 L of wate

To obtain the molarity, calculate the concentration in g/dm3 and then concentration in mol/dm3

Concentration in g/dm3  = 525 g/ 3.50 L

= 525g/ 3.50 dm3

= 150g/dm3 of SnF4

Concnetration in mol/dm3

concentration in mol/dm3 = concentration in g/dm3 / Relative molecular mass of SnF2

RMM of SnF2 = ( 119 + 19*2) = 157 g/mol

= 150g/dm3 / 157g/mol

= 0.9554 mol/dm3 of solution.

The molarity of the solution is therefore 0.9554mol/dm3

im not exactly sure but i think its b!

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

neutral atoms of elements after calcium contain d electrons. the energy of d orbitals of a particular main shell lies between the energy of the s and p orbitals of the next main shell. for example, electrons in the have energy higher than those in the orbital while lower than those of the orbital.

by the aufbau principle, electrons fill orbitals one at a time, starting from those of the lowest energy. the orbital is therefore filled right after orbitals and before orbitals.  

potassium has electron configuration and calcium . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the and should be highlighted as well.