D. To answer this question refer to the periodic table and think logically about it. Adding one proton increases the atomic number so you go along the row to Nitrogen. If you lose one neutron then the atomic mass decreases by 1 so 14-1 is 13.
Answer : The mass of sodium bromide added should be, 18.3 grams.
Explanation :
Molality : It is defined as the number of moles of solute present in kilograms of solvent.
Formula used :

Solute is, NaBr and solvent is, water.
Given:
Molality of NaBr = 0.565 mol/kg
Molar mass of NaBr = 103 g/mole
Mass of water = 315 g
Now put all the given values in the above formula, we get:


Thus, the mass of sodium bromide added should be, 18.3 grams.
Answer: Which Group 1A elements are less dense than pure water at 4 degrees C? Li Na K. How does density vary with temperature? Temperature up, density down.
Explanation:
The new pressure inside the syringe will be 1.25 atm
<h3>Gas law</h3>
At constant temperatures, the volume of a gas is inversely proportional to its pressure.
Thus: P1V1 = P2V2
In this case, P1 = 3.0 atm, V1 = 89.6 mL, V2 = 215 mL
P2 = P1V1/V2
= 3 x 89.6/215
= 1.25 atm
More on gas laws can be found here: brainly.com/question/1190311
Answer:
the initial concentration of SCN- in the mixture is 0.00588 M
Explanation:
The computation of the initial concentration of the SCN^- in the mixture is as follows:
As we know that

As it is mentioned in the question that KSCN is present 10 mL of 0.05 M
So, the total milimoles of SCN^- is
= 10 × 0.05
= 0.5 m moles
The total volume in mixture is
= 45 + 10 + 30
= 85 mL
Now the initial concentration of the SCN^- is
= 0.5 ÷ 85
= 0.00588 M
hence, the initial concentration of SCN- in the mixture is 0.00588 M