Which element gains two electrons to fill its outermost energy level?

You are given a 1.00 molal solution of an unknown solute dissolved in water and told that you must determine if the solute is a

aniked [119]

Answer: Yes, the solute is a weak electrolyte

Explanation:

Depression in freezing point is given by:

$\Delta T_f=i\times K_f\times m$

$\Delta T_f=T_f^0-T_f=(0-(-2.05))^0C=2.05^0C$ = Depression in freezing point

i= vant hoff factor = ?

$K_f$ = freezing point constant = $1.86^0C/m$

m= molality

$\Delta T_f=i\times K_f\times m$

$2.05=i\times 1.86\times 1$

$i=1.10$

As i for non electrolytes is 1, the given compound must be an electrolyte and a weak electrolyte as the value is only slightly greater than 1.

8 0

3 years ago

A student is asked to determine the molarity of a strong base by titrating it with 0.250 M solution of H2SO4. The students is in

Hoochie [10]

Answer: The concentration of hydroxide ions in the strong base solution is 0.625 M

Explanation:

To calculate the molarity of solution, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}\times 1000}{\text{Volume of solution (in mL)}}$ .......(1)

For sulfuric acid:

Molarity of solution = 0.250 M

Volume of solution = (30.00 - 5.00) mL = 25.00 mL

Putting values in equation 1, we get:

$0.250M=\frac{\text{Moles of sulfuric acid}\times 1000}{25.00}\\\\\text{Moles of sulfuric acid}=\frac{0.250\times 25.00}{1000}=0.00625moles$

1 mole of sulfuric acid produces 2 moles of hydrogen ions and 1 mole of sulfate ions

Moles of hydrogen ions = $(2\times 0.00625)=0.0125moles$

At pH = 7

Moles of hydrogen ions = Moles of hydroxide ions = 0.0125 moles

Now, calculating the hydroxide ions in the base solution by using equation 1, we get:

Moles of hydroxide ions = 0.0125 moles

Volume of base solution = 20.0 mL

Putting values in equation 1, we get:

$\text{Molarity of }OH^-\text{ ions}=\frac{0.0125mol\times 1000}{20.0}\\\\\text{Molarity of }OH^-\text{ ions}=0.625M$

Hence, the concentration of hydroxide ions in the strong base solution is 0.625 M

5 0

3 years ago

Select the structure that corresponds

Lostsunrise [7]

Answer:

C. both

Explanation:

8 0

2 years ago

Name two landforms created from deposits by rivers.

pav-90 [236]

Alluvial fans and deltas are formed.

5 0

3 years ago

How do i know if a reaction is exo/endothermic?? help please.

goblinko [34]

Answer:

Explanation: in exothermic reaction heat is released out

In endothermic reaction heat is absorbed

3 0

3 years ago