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3 years ago

How is the kinetic energy of the particles that make up a substance different

Physics

1 answer:

Feliz [49]3 years ago

5 0

Answer:

the kinetic energy is less after a substance changes from liquid to gas

Explanation:

the kinetic energy is greater after a substance changes from a solid to liquid

You might be interested in

What is the momentum of a compact car that is 750 kg and is travelling 30 m/s?

MakcuM [25]

The formula for momentum is p = mv, where p is momentum, m is mass, and v is velocity.

To solve for p, plug in 750 kg for mass and 30 m/s for velocity. • is a multiplication symbol

p = mv
p = 750kg • 30m/s
p = 22500 kg•m/s

5 0

3 years ago

A car is traveling at a speed of 20m/s and has a mass of 1200kg how much kinetic energy does it have

Oxana [17]

Answer:

Explanation:

The formula for Kinetic Energy is

$KE=\frac{1}{2}mv^2$ . Filling in:

$KE=\frac{1}{2}(1200)(20)^2$ It looks like we only need 1 significant digit here but I'll give you 2 and you can round how you want.

KE = 2.4 × 10⁵ J

4 0

3 years ago

An aluminum calorimeter with a mass of 100 g contains 250 g of water. The calorimeter and water are in thermal equilibrium at 10

Alexeev081 [22]

Answer:

a) $c=1822.3214\ J.kg^{-1}.K^{-1}$

b) This value of specific heat is close to the specific heat of ice at -40° C and the specific heat of peat (a variety of coal).

c) The material is peat, possibly.

d) The material cannot be ice because ice doesn't exists at a temperature of 100°C.

Explanation:

Given:

mass of aluminium, $m_a=0.1\ kg$

mass of water, $m_w=0.25\ kg$

initial temperature of the system, $T_i=10^{\circ}C$

mass of copper block, $m_c=0.1\ kg$

temperature of copper block, $T_c=50^{\circ}C$

mass of the other block, $m=0.07\ kg$

temperature of the other block, $T=100^{\circ}C$

final equilibrium temperature, $T_f=20^{\circ}C$

We have,

specific heat of aluminium, $c_a=910\ J.kg^{-1}.K^{-1}$

specific heat of copper, $c_c=390\ J.kg^{-1}.K^{-1}$

specific heat of water, $c_w=4186\ J.kg^{-1}.K^{-1}$

Using the heat energy conservation equation.

The heat absorbed by the system of the calorie-meter to reach the final temperature.

$Q_{in}=m_a.c_a.(T_f-T_i)+m_w.c_w.(T_f-T_i)$

$Q_{in}=0.1\times 910\times (20-10)+0.25\times 4186\times (20-10)$

$Q_{in}=11375\ J$

The heat released by the blocks when dipped into water:

$Q_{out}=m_c.c_c.(T_c-T_f)+m.c.(T-T_f)$

where

$c=$ specific heat of the unknown material

For the conservation of energy : $Q_{in}=Q_{out}$

so,

$11375=0.1\times 390\times (50-20)+0.07\times c\times (100-20)$

$c=1822.3214\ J.kg^{-1}.K^{-1}$

This value of specific heat is close to the specific heat of ice at -40° C and the specific heat of peat (a variety of coal).

The material is peat, possibly.

The material cannot be ice because ice doesn't exists at a temperature of 100°C.

7 0

2 years ago

Whiat is quantum numbers describes the size and energy of an orbital?

Levart [38]

Answer:

The answer is the principal Quantum number (n)

Explanation:

The principal quantum number is one of the four quantum numbers associated with an atom.

It is denoted by a number n=1,2,3,4 etc

It tells both size (directly) and energy (indirectly) of an orbital.

When n=1 means it is the closest to the nucleus and is the smallest orbital and with increase in principal quantum number, it depicts that size of the orbital is increasing.

It tells the energy of the orbital as well as smaller number means less distance from nucleus and having less energy. Since electrons requires to absorb energy to jump into higher orbitals making n=2,3,4 etc. Thus electrons in the orbitals with higher n number indicates higher energy orbitals.

7 0

3 years ago

According to the law of conservation of matter, what number must be the same on each side of a chemical equation?

olga2289 [7]

Answer:

4. The number of atoms of each element

Explanation:

Why is 1 wrong?

The number of substances (i.e. number of mols of substances) do not have to be the same. For instance, 2 mol of water reacts with 1 mol of oxygen to form 2 mol of water. Obviously the numer of substances is not conserved. Thus, it isn't a requirement.

Why is 2 wrong?

The number of chemical symbols do not mean anything. They do not tell us anything about the quantity of matter, they only tell us about the elements that are involved in the reaction.

Why is 3 wrong?

Once again, the number of chemical formulas are meaningless.

Why is 4 correct?

The number of atoms are always conserved as atoms cannot be broken or created.

Possible confusion...

The number of atoms are always conserved but the number of molecules may not always be conserved.

Why? As 2 atoms may be a molecule on the reactant side and 4 atoms may become a molecule on the product size, causing the number of molecules to reduce by half, while the number of atoms remain constant.

Hope that makes sense!

7 0

3 years ago