Answer: -
15.55 M
35.325 molal
Explanation: -
Let the volume of the solution be 1000 mL.
Density of nitric acid = 1.42 g/ mL
Total Mass of nitric acid Solution = Volume of nitric acid x Density of nitric acid
= 1000 mL x 1.42 g/ mL
= 1420 g.
Percentage of HNO₃ = 69%
Amount of HNO₃ = 
= 979.8 g
Molar mass of HNO₃ = 1 x 1 + 14 x 1 + 16 x 3 = 63 g /mol
Number of moles of HNO₃ = 
= 15.55 mol
Molarity is defined as number of moles per 1000 mL
We had taken 1000 mL as volume and found it to contain 15.55 moles.
Molarity of HNO₃ = 15.55 M
Mass of water = Total mass of nitric acid solution - mass of nitric acid
= 1420 - 979.8
= 440.2 g
So we see that 440.2 g of water contains 15.55 moles of HNO₃
Molality is defined as number of moles of HNO₃ present per 1000 g of water.
Molality of HNO₃ = 
= 35.325 molal
I think the answer is approximately 4.12 billion years since the amount of years is 4.543 billion years
Answer:
The value of an integer x in the hydrate is 10.
Explanation:

Molarity of the solution = 0.0366 M
Volume of the solution = 5.00 L
Moles of hydrated sodium carbonate = n


Mass of hydrated sodium carbonate = n= 52.2 g
Molar mass of hydrated sodium carbonate = 106 g/mol+x18 g/mol



Solving for x, we get:
x = 9.95 ≈ 10
The value of an integer x in the hydrate is 10.
Explanation:
Element X forms a chloride with the formula XCl 2 , which is a solid with a high melting point. X would most likely be in the same group of the Periodic Table as. (a) Na (b) Mg (c) Al (d) Si. the answer is Mg .
Answer:
C. Carbon
Explanation:
Carbon has an electronegativity of 2.55, followed by Tin at 1.96, Silicon at 1.90 and the least electronegative would be Lead at 1.87.