All categories

3 years ago

Sally has touched a hot pan on the stove and burnt her hand. This example shows what type of heat transfer?

Chemistry

1 answer:

Minchanka [31]3 years ago

6 0

Answer:

Transfer of Heat

You might have observed that a frying pan becomes hot when kept on a flame. It is because the heat passes from the flame to the utensil. When the pan is removed from the fire, it slowly cools down. Why does it cool down? The heat is transferred from the pan to the surroundings. So you can understand that in both cases, the heat flows from a hotter object to a colder object. In fact, in all cases heat flows from a hotter object to a colder object.

Explanation:

please make me as brainleist

You might be interested in

Exactly how much time must elapse before 16 grams of potassium-42decays, leaving 2 grams of the original isotope?(1) 8 × 12.4 ho

AleksandrR [38]

The answer is (3) 3 × 12.4 hours

To calculate this, we will use two equations:
$(1/2) ^{n} =x$
$t_{1/2} = \frac{t}{n}$
where:
n - number of half-lives
x - remained amount of the sample, in decimals
 $t_{1/2}$ - half-life length
t - total time elapsed.

First, we have to calculate x and n. x is remained amount of the sample, so if at the beginning were 16 grams of potassium-42, and now it remained 2 grams, then x is:
2 grams : x % = 16 grams : 100 %
x = 2 grams × 100 percent ÷ 16 grams
x = 12.5% = 0.125

Thus:
 $(1/2) ^{n} =x$
 $(0.5) ^{n} =0.125$
$n*log(0.5)=log(0.125)$
$n= \frac{log(0.5)}{log(0.125)}$
$n=3$

It is known that the half-life of potassium-42 is 12.36 ≈ 12.4 hours.
Thus:
 $t_{1/2} = 12.4$
 $t_{1/2} *n = t$
 $t= 12.4*3$

Therefore, it must elapse 3 × 12.4 hours before 16 grams of potassium-42 decays, leaving 2 grams of the original isotope

7 0

3 years ago

Read 2 more answers

How are Parkinson's disease and ALS similar?

Diano4ka-milaya [45]

Answer:

Both diseases affect the control of voluntary muscles.

Explanation:

Parkinson's disease is a progressive brain disease that affects movement. It affects the nerve cells that produce dopamine in the part of the brain called substantia nigra. The symptoms include shaking, stiffness, and difficulty with walking, balance, and coordination. Symptoms get worse with time, often leaving people with difficulty walking and talking.

ALS (amyotrophic lateral sclerosis) is a progressive nervous system disease that affects nerve cells in the brain and spinal cord. The first symptoms usually involve muscle weakness, and as the disease progresses, it results in the loss of muscle control.

Scientists don't know the exact cause of these diseases. As the cause is not known, there is no exact way to prevent them. There is no cure for them, either. The treatment is focused on the management of symptoms.

This is why the third option is the correct one.

4 0

3 years ago

What’s a conjugative Bas of OH-

LiRa [457]

Answer:

the answer is O²- hopefully

8 0

3 years ago

Isotopes that decay with a nuclear break-up and emit a significant amount of energy are said to be ________.

podryga [215]

Answer to this is Radioactive isotopes.

Isotopes are the species of the same element having different atomic masses that means the number of protons remains the same but number of neutrons do differ. For example $_{1}^{2}\textrm{H}$ and $_{1}^{3}\textrm{H}$ are the two isotopes of Hydrogen ( $_{1}^{1}\textrm{H}$ ).

Radioactive isotopes are the isotopes which release some kind of energy in the form of alpha particles, beta particles or gamma radiation. Examples of each of the decay processes are :

Alpha Decay: In this decay one alpha particle having atomic mass 4 and atomic number 2 or we can say a He molecule will come out. $_{Z}^{A}\textrm{X}\rightarrow _{Z-2}^{A-4}\textrm{Y}+_{2}^{4}\alpha$

Beta Decay: In this decay a $\beta$ particle is emitted increasing the atomic number of the reactant by 1 unit.

$_{Z}^{A}\textrm{X}\rightarrow _{Z+1}^{A}\textrm{Y}+_{-1}^{0}\beta$

Gamma Radiation: In this type of reaction only radiation is emitted out which does not change the original molecule.

$_{Z}^{A}\textrm{X}\rightarrow _{Z}^{A}\textrm{X}+\gamma\text{ radiation}$

3 0

3 years ago

What is the barycenter of the moon and the earth

kirill [66]

Answer:

The barycenter is the point in space around which two objects orbit. For the Moon and Earth, that point is about 1000 miles (1700 km) beneath your feet, or about three-quarters of the way from the Earth's center to its surface.

Explanation:

6 0

3 years ago