Answer:- 2.92 kJ of heat is released.
Solution:- We have water at 100 degree C and it's going to be cool to 15 degree C.
So, change in temperature, 
= 15 - 100 = -85 degree C
mass of water, m = 8.2 g
specific heat of water, c = 
The equation used for solving this type of problems is:
Let's plug in the values in the equation and solve it for q which is the heat energy:
q = (8.2)(4.184)(-85)
q = -2916.248 J
They want answer in kJ. So, let's convert J to kJ and for this we divide by 1000.
q = -2.92 kJ
Negative sign indicates the heat is released. So, in the above process of coiling of water, 2.92 kJ of heat is released.
KE = 0
<h3>Further explanation </h3>
Energy is the ability to do work
Energy because its motion is expressed as Kinetic energy (KE) which can be formulated as:
So for two objects that have the same speed, the greater the mass of the object, the greater the kinetic energy
The stone in hand is in a motionless state (at rest) so that its velocity (v) = 0, so it has no kinetic energy
But this stone can have <em>potential energy that is gained due to its height</em>
1000 g of feathers is the least dense
Given the solubility of strontium arsenate is 0.0480 g/l . we have to convert it into mol/L by dividing it over molar mass (540.7 g/mol)
Molar solubility = 0.0480 / 540.7 = 8.9 x 10⁻⁵ mol/L
Dissociation equation:
Sr₃(AsO₄)₂(s) → 3 Sr²⁺(aq) + 2 AsO₄³⁻(aq)
3 s 2 s
Ksp = [Sr²⁺]³ [AsO₄³⁻]²
= (3s)³ (2s)²
= 108 s⁵
Ksp = 108 (8.9 x 10⁻⁵) = 5.95 x 10⁻¹⁹
Question:
A student weighed an empty graduated cylinder. It weighed 35.86 g. She then carefully added water to the graduated cylinder until it reached the 7.5 mL mark. When she weighed the graduated cylinder again, this time with the 7.5 mL of water in it, it weighed 43.18 g. What was this student's experimental density of water?
Answer:
0.976 g/mL
Explanation:
Weight of empty cylinder = 35.86g
Volume of water = 7.5mL
Weight of cylinder + water = 43.18g
Experimental density = ?
Density of water = Mass of water / volume of water
Mass of water = (Weight of cylinder + water) - Weight of empty cylinder
Mass of water = 43.18 - 35.86 = 7.32g
Density = 7.32 / 7.5 = 0.976 g/mL
