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2 years ago

Synthetic, or man-made, elements typically exist for only a short time

1 answer:

8 0

This is true. Elements past lead are radioactive, because the repulsive force of the protons cannot be overpowered by the “gluing” ability of neutrons (remember, likes repel). As more and more protons are added, generally, the elements become more unstable; for example, Bismuth, right next to lead on the Periodic Table, is radioactive, but the half life of this element is about a billion times longer than the current age of the universe, but Oganesson, element number 118, has a half life of fractions of a second.

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What is science about?

Olin [163]

Answer:

Science is the study of the nature and behavior of natural things and the knowledge that we obtain about them. ... A science is a particular branch of science such as physics, chemistry, or biology. Physics is the best example of a science which has developed strong, abstract theories.

Explanation:

8 0

2 years ago

Read 2 more answers

Which of the following is true?

Tomtit [17]

Answer:

a. A reaction in which the entropy of the system increases can be spontaneous only if it is endothermic.

Explanation:

The change in free energy (ΔG) that is, the energy available to do work, of a system for a constant-temperature process is:

$ΔG = ΔH - TΔS$

When ΔG < 0 the reaction is spontaneous in the forward direction.

When ΔG > 0 the reaction is nonspontaneous. The reaction is

spontaneous in the opposite direction.

When ΔG = 0 the system is at equilibrium.

If both ΔH and ΔS are positive, then ΔG will be negative only when the TΔS term is greater in magnitude than ΔH. This condition is met when T is large.

3 0

2 years ago

Which of the following factors does NOT affect surface currents?

lubasha [3.4K]

Answer: B

Explaining: surface currents are caused by wind density affects deep ocean currents

4 0

2 years ago

Read 2 more answers

A 10.-liter flask at a given temperature and pressure contains 6.0 × 1023 molecules of hydrogen gas. Under the same conditions o

valentina_108 [34]

Answer:

The same number of molecules, 6.0 × 10²³ molecules.

Explanation:

The amount of any given gas that can be stored in a container depends on the temperature, pressure and volume of the container. It does not depend on the nature (or identity) of the gas.

So if a 10-liter flask contains 6.0 × 10²³ molecules of hydrogen gas, it will contain the same amount of molecules of any other gas when temperature and pressure remain constant.

6 0

2 years ago

Zn-64 = 48.63%

Ann [662]

Answer:

A = 65.46 u

Explanation:

Given that,

The composition of zinc is as follows :

Zn-64 = 48.63%

Zn-66 = 27.90%

Zn-67 = 4.10%

Zn-68 = 18.75%

Zn-70 = .62%

We need to find the average atomic mass of the given element. It can be solved as follows :

$A=\dfrac{48.63\times 64+27.90\times 66+4.1\times 67+18.75\times 68+0.62\times 70}{100}\\A=65.46\ u$

So, the average atomic mass of zinc is 65.46 u.

5 0

2 years ago