Ask question

Ask question

All categories

3 years ago

5

C. Another radioisotope of americium exists which has an atomic mass of 242.

1 answer:

ollegr [7]3 years ago

7 0

Answer:

1 g

Explanation:

The half-life of Am-242 (16 h) is the time it takes for half of it to disappear.

We can make a table of the mass left after each half-life.

$\begin{array}{cccc}\textbf{No. of} & & \textbf{Percent} & \textbf{Mass}\\\textbf{Half-lives} & \textbf{Time/h} & \textbf{Remaining} & \textbf{Remaining/g}\\0& 0 & 100 & 8\\1 & 16 &50 & 4\\2 & 32 & 25 & 2\\3 & 48 & 12.5 & 1\\4 & 64 & 6.25 & 0.5\\\end{array}$

The mass remaining after 48 h is 1 g.

You might be interested in

What are 3 household substances that contain acids and say why are they useful

Nonamiya [84]

Answer:

battery. you use it for your remotes. vinegar. you use vinegar for cooking of cleaning. nail polish remover. you use this for removing nail polish

6 0

3 years ago

The reaction a(g)⇌b(g) has an equilibrium constant of 5.8 and under certain conditions has q = 336. part a what can you conclude

Vika [28.1K]

Answer:

The answer is "As $Q=336$ , at high-temperature $\Delta G_{rxn}>0$ and When $K>1,$ $\Delta G^{\circ}_{rxn}>0$ ."

Explanation:

The equation for the reaction is:

$A(g) \leftrightharpoons B(g)$

$K=5.8\\\\Q=336$

At equilibrium,

$\Delta G^{\circ}_{rxn}>0$ $=-RT \ln \ K$

When k=5.8(>1), the value of $\ln k$ would be positive

So, $\Delta G^{\circ}_{rxn}$ is negative (< 0)

So if K > l, $\Delta G^{\circ}_{rxn}$

If the reaction is not in equilibrium so the equation is :

$\Delta G_{rxn}>0$ = $\Delta G^{\circ}_{rxn}$ $+RT \ln Q$

Substituting the expression:

$\Delta G_{rxn}>0$ $= (-RT \ln K) + RT \ln Q$

$= RT(\ln Q- \ln K)\\= RT(\ln (336)-\ln (5.8))\\= RT(4.06)$

It is the positive value for all temperatures.

So, As Q = 336, at the high temperature $\Delta G_{rxn}>0$ .

5 0

3 years ago

In the chemical formula below, how many H atoms are present?<br> 5NH4OH

Norma-Jean [14]

Answer:

5 H atoms per NH4OH

Explanation:

5NH4OH

NH4OH is a chemical formula. It has 5 H atoms per each molecule. NH<em><u>4</u></em>O<em><u>H</u></em>

<em><u /></em>

5NH4OH means 5 molecules (or moles) of NH4OH. But the question asks per chemical formula, so 5 is correct,

There would be 5x4 or 20 atoms of H is 5 molecules of NH4OH.

8 0

2 years ago

What conditions must be present for a rock to turn into a metamorphic rock

Brut [27]

Igneous that can be changed by heat and pressure which can change the form of the rock

3 0

3 years ago

Which substance is needed in order for this biochemical reaction to occur?

Anna35 [415]

What biochemical reaction??

4 0

4 years ago