At a certain temperature, the ph of a neutral solution is 7.43. what is the value of kw at that temperature? express your answer numerically using two significant figures.

The formula for Kw is:

Kw= [H]*[OH]

where [H] and [OH] are concentrations 

We are given the pH so we can calculate the [H] concentration from the formula:
pH=-log[H] 
7.43 = -log[H]

[H] = 3.715x10^-8 M

In neutral solution, [H] = [OH], therefore: 

[OH]= 3.715x10^-8 M

Calculating Kw:

Kw = (3.715x10^-8)*( 3.715x10^-8)

Kw = 1.38 x 10^-15 

The value of the ionic product of water at neutral pH of 7.43 has been  1.38 .

has the ionic product of water and varies at different temperatures.

The ionic product can be given as:

The hydrogen ion concentration at pH 7.43 will be:

pH = -log [Hydrogen ion concentration]

7.43 =  -log [Hydrogen ion concentration]

Hydrogen ion concentration = 3.715 M

At neutral pH, the hydrogen ion concentration is equal to hydroxide ion concentration.

= 3.715   3.715 M

= 1.38 .

The value of the ionic product of water at neutral pH of 7.43 has been  1.38 .

For more information about ionic product, refer to the link:

link

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.