Answer:
-86.02 kJ/ mole
Explanation:
The moles of the acid used = Molarity × Volume (L) =
= 0.50 (0.0372 L)
= 0.0186 moles
The heat released = -1.6 kJ
∴ 0.0186 moles neutralization of HA heat is: -1.6 kJ
The molar heat of neutralization due to one mole of the unknown acid = -1.6/0.0186
= -86.02 kJ/ mole
Answer:
Total volume after adding crystal = 26.7 mL
Explanation:
Given data:
Density of crystal = 2.65 g/mL
Mass of sample = 4.46 g
Volume of water = 25.0 mL
Volume after adding crystal = ?
Solution:
First of all we will calculate the volume of crystal.
d = m/v
2.65 g/mL = 4.46 g/ v
v = 4.46 g/2.65 g/mL
v = 1.7 mL
Total volume after adding crystal = Volume of water + Volume of metal
Total volume after adding crystal = 25.0 mL + 1.7 mL
Total volume after adding crystal = 26.7 mL
<span>when it comes to adding or subtracting numbers, his final answer should have the same number of decimal places as the least precise value.
For example if you add 2 numbers; 10.443 + 3.5 , 10.443 has 3 decimal places and 3.5 has only one decimal place.
Therefore 3.5 is the less precise value.
So when adding these 2 values the final answer should have only one decimal place.
after adding we get 13.943 but it can have upto one decimal place. then the second decimal place is less than 5 so the answer should be rounded off to 13.9.
the answer is the same number of decimal places as the least precise value</span>
To determine the number of potassium laid side by side by a given distance, we simply divide the total distance to the diameter of each atom. The diameter is twice the radius of the atom. We calculate as follows:
number of atoms = 4770 / 231x10^-12 = 2.06x10^13 atoms
It can be made true by changing "cannot" to "can".