Calculate the density of a 0.845 m H2SO4 solution that has a molarity of 0.821 M.

In solids, the particles of matter are not in constant motion.

Vsevolod [243]

True because in a solid particles dont move so it wouldn't be in a constant motion.

5 0

3 years ago

Read 2 more answers

I will give brainliest!! How long is the pencil? Make sure to use the appropriate amount of significant figures.

8090 [49]

Answer: Option (c) is the correct answer.

Explanation:

The bottom of pencil is placed at the starting point of scale. Whereas the tip of pencil depicts the end point of its length.

The bottom of pencil is at 0 mm and tip of pencil is at 18.73 mm. The appropriate amount of significant figures is 18.73 mm.

Therefore, we can conclude that out of the given options, pencil is 18.73 mm long.

5 0

4 years ago

A chemist prepares a solution of magnesium chloride MgCl2 by measuring out 49.mg of MgCl2 into a 100.mL volumetric flask and fil

Flura [38]

Answer: Molarity of $Cl^-$ anions in the chemist's solution is 0.0104 M

Explanation:

Molarity : It is defined as the number of moles of solute present per liter of the solution.

Formula used :

$Molarity=\frac{n\times 1000}{V_s}$

where,

n= moles of solute

$Moles=\frac{\text{Given mass}}{\text{Molar mass}}=\frac{0.049g}{95g/mol}=5.2\times 10^{-4}moles$

$V_s$ = volume of solution in ml = 100 ml

Now put all the given values in the formula of molarity, we get

$Molarity=\frac{5.2\times 10^{-4}moles\times 1000}{100ml}=5.2\times 10^{-3}mole/L$

Therefore, the molarity of solution will be $5.2\times 10^{-3}mole/L$

$MgCl_2\rightarrow Mg^{2+}+2Cl^-$

As 1 mole of $MgCl_2$ gives 2 moles of $Cl^-$

Thus $5.2\times 10^{-3}$ moles of $MgCl_2$ gives = $\frac{2}{1}\times 5.2\times 10^{-3}=0.0104$

Thus the molarity of $Cl^-$ anions in the chemist's solution is 0.0104 M

6 0

3 years ago

Some radioactive nuclides have very short half-lives, for example, I-31 has a half-life of approximately 8 days. Pu-234, by comp

lorasvet [3.4K]

Answer:

Here's what I find.

Explanation:

Iodine-131

Iodine-131 is both a beta emitter and a gamma emitter.

$_{53}^{131}\text{I}\longrightarrow \, _{54}^{131}\text{Xe} +\, _{-1}^{0}\text{e} +\, _{0}^{0}\gamma$

About 90 % of the energy is β-radiation and 10 % is γ-radiation. Both forms are highly energetic.

The main danger is from ingestion. The iodine concentrates in thyroid gland, where the β-radiation destroys cells up to 2 mm from the tissues that absorbed it.

Both the β- and γ-radiation cause cell mutations that can later become cancerous. Small doses, such as those absorbed from the nuclear disasters in the Ukraine and Japan, can cause cancers years after the original iodine has disappeared.

Plutonium-239

Plutonium-239 is an alpha emitter.

$_{94}^{239}\text{U} \longrightarrow \, _{92}^{235}\text{Xe} + \, _{2}^{4}\text{He}$

Alpha particles cannot penetrate the skin, so external exposure isn't much of a health risk.

However, they are extremely dangerous when they are inhaled and get inside cells. They travel first to the blood or lymph system and later to the bone marrow and liver, where they cause up to 1000 times more chromosomal damage than beta or gamma rays.

It takes about 20 years for plutonium to be eliminated from the liver around 50 years for from the skeleton, so it has a long time to cause damage.

6 0

3 years ago

HELP PLS (CHEMISTRY)

IRINA_888 [86]

The first most obvious thing to note is when naming transitional metals, you have to state its charge with roman numerals (except for 1 if I remember correctly). For example, Iron (lll), iron has a charge of 3.

4 0

3 years ago