Answer:
The answer to your question is Ke = 2240 J
Explanation:
Data
mass of the object = 20 kg
mass of the girl = 50 kg
speed = 8 m/s
Kinetic energy = Ke = ?
Formula
Ke = 1/2 mv²
Process
Kinetic energy is due to the movement of an object.
1.- Calculate the total mass
Total mass = 20 + 50 = 70 kg
2.- Substitution
Ke = 1/2(70)(8)²
3.- Simplification
Ke = 1/2(4480)
4.- Result
Ke = 2240 J
Answer: The answer is S = 0.1528 cal/g °C
Explanation:
By the law of conservation of energy, energy is neither created nor destroyed.
So, energy lost by metal pieces is equal to the energy gained by water in the calorimeter.
Specific heat of water is 1 cal/g °C
⇒ heat energy Q = mSΔT, where m = mass of a substance
S = specific heat
ΔT = change in temperature
Now, the heat lost by metal piece, Q = 72×S×(96-31)
= 4680×S cal
Heat gained by water, Q = 130×1×(31-25.5)
= 715 cal
⇒ 4680×S = 715.
⇒ S = 0.1528 cal/g °C.
1.35 mole of K₂SO₄ contain 2.7 moles of cation.
Cations are positive ions. They are the ions of metallic elements.
To obtain the answer to the question, we'll begin by calculating the number of mole of cations in 1 mole of K₂SO₄.
K₂SO₄ (aq) —> 2K⁺ (aq) + SO₄²¯ (aq)
<h3>Cation => K⁺</h3>
From the balanced equation above,
1 mole of K₂SO₄ contains 2 moles of K⁺ (i.e cation).
Finally, we shall determine the number of mole of cation in 1.35 mole of K₂SO₄. This can be obtained as follow:
1 mole of K₂SO₄ contains 2 moles of K⁺ (i.e cation).
Therefore, 1.35 mole of K₂SO₄ will contain = 1.35 × 2 = 2.7 moles of K⁺ (i.e cation).
Hence, we can conclude that 1.35 mole of K₂SO₄ contain 2.7 moles of cation
Learn more: brainly.com/question/24707125
<u>The frequency of </u><u>collisions </u><u>between the two reactants increases as the </u><u>concentration </u><u>of the reactants increases</u>. When collisions happen, they don't always cause a reaction (atoms misaligned or insufficient energy, etc.). Higher concentrations result in more collisions and reaction opportunities.
Increasing a reactant's surface area increases the frequency of collisions and thus the reaction rate. The surface area of several smaller particles is greater than that of a single large particle. The greater the available surface area for particles to collide, the faster the reaction will occur.
<h3>How does concentration affect the rate of collisions between reactants?</h3>
Thus, we can conclude that by increasing the concentration of Mg in the reaction mixture we increase the rate of collisions between the reactants in this reaction.
<h3>What does the half reaction of an oxidation-reduction reaction show?</h3>
Iron gains electrons in the half reaction of an oxidation-reduction reaction. What does iron's electron gain mean? It has been reduced. Predict the product that will precipitate out of the reaction using the solubility rules and the periodic table.
Learn more about collisions of particles:
brainly.com/question/14897392
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