On the periodic table it is the number on the bottom of the element.
<span>If you know the amount of neutrons you can add it to the number of protons to find the atomic mass NUMBER, which is a good approximate of the atomic mass. </span>
Answer:
- <u>Yes, it is 14. g of compound X in 100 ml of solution.</u>
Explanation:
The relevant fact here is:
- the whole amount of solute disolved at 21°C is the same amount of precipitate after washing and drying the remaining liquid solution: the amount of solute before cooling the solution to 21°C is not needed, since it is soluble at 37°C but not soluble at 21°C.
That means that the precipitate that was thrown away, before evaporating the remaining liquid solution under vacuum, does not count; you must only use the amount of solute that was dissolved after cooling the solution to 21°C.
Then, the amount of solute dissolved in the 600 ml solution at 21°C is the weighed precipitate: 0.084 kg = 84 g.
With that, the solubility can be calculated from the followiing proportion:
- 84. g solute / 600 ml solution = y / 100 ml solution
⇒ y = 84. g solute × 100 ml solution / 600 ml solution = 14. g.
The correct number of significant figures is 2, since the mass 0.084 kg contains two significant figures.
<u>The answer is 14. g of solute per 100 ml of solution.</u>
Electronnegativity increase because the number of charges on the nucleus increases. Which attracts the bonding amount of electrons more.
The time elapsed when the ball placed above the concave mirror and the image formed would be at the same location is 0.55 s.
<h3>Image distance</h3>
The position of the image formed is determined using the followimg mirror formula;
where;
- f is the focal length of the mirror
- v is the image distance
- u is the object distance
f = R/2
f = 1.5/2
f = 0.75 m
When the ball and its image is in the same position, u = v
The position of the ball is calculated as;
<h3>Time of motion of the ball</h3>
The time taken for the ball to travel the caluclated distance is determined as;
h = ut + ¹/₂gt²
1.5 = 0 + ¹/₂(9.8)t²
1.5 = 4.9t²
t² = 1.5/4.9
t² = 0.306
t = 0.55 s
Thus, the time elapsed when the ball and its image are at the same location is 0.55 s.
Learn more about concave mirror here: brainly.com/question/7512320
