Ask question

Ask question

All categories

MA_775_DIABLO [31]

3 years ago

14

A solution which is 38.0% w/w in k2cro4 has a specific gravity of 1.37. calculate the concentration in terms of molarity of chro

mate ion.

1 answer:

Makovka662 [10]3 years ago

7 0

When in aqueous solution, K2CrO4 dissociates into ions. It dissociates into:

K2CrO4 = 2K+1 + CrO4-1

We do as follows:

Molarity = mol / L = 0.38 g/g solution ( 1.37 g/mL ) ( 1 mol / 194.19 g ) ( 1 mol CrO4-1 / 1 mol K2CrO4 ) ( 1000 mL / 1 L ) = 2.68 M

You might be interested in

What are the coordinates to this?

Hoochie [10]

Answer:

D (-5,-2) E (0,-2), and F (-4,-6)

Step-by-step explanation:

hope it helps

4 0

3 years ago

Read 2 more answers

Convert the following measurements:

satela [25.4K]

Step-by-step explanation:

a.3.4cm

b.23000l

c.0.016g

d.3000m

e.2000mg

4 0

3 years ago

PLEASE HELP- Tito solved this equation (Click picture) Which of the following properties did he use? Check all that apply.

gayaneshka [121]

Where's the picture??????????????

6 0

3 years ago

Use technology or a z-score table to answer the question.

Alik [6]

Answer:

The second choice: Approximately $65.2\%$ of the pretzel bags here will contain between 225 and 245 pretzels.

Step-by-step explanation:

This explanation uses a z-score table where each $z$ entry has two decimal places.

Let $\mu$ represent the mean of a normal distribution of variable $X$ . Let $\sigma$ be the standard deviation of the distribution. The z-score for the observation $x$ would be:

$\displaystyle z = \frac{x - \mu}{\sigma}$ .

In this question,

$\mu = 240$ .
$\sigma = 9.3$ .

Calculate the z-score for $x_1 = 225$ and $x_2 = 245$ . Keep in mind that each entry in the z-score table here has two decimal places. Hence, round the results below so that each contains at least two decimal places.

$\begin{aligned} z_1 &= \frac{x_1 - \mu}{\sigma} \\ &= \frac{225 - 240}{9.3} \approx -1.61\end{aligned}$ .

$\begin{aligned} z_2 &= \frac{x_2 - \mu}{\sigma} \\ &= \frac{245 - 240}{9.3} \approx 0.54\end{aligned}$ .

The question is asking for the probability $P(225 \le X \le 245)$ (where $X$ is between two values.) In this case, that's the same as $P(-1.61 \le Z \le 0.54)$ .

Keep in mind that the probabilities on many z-table correspond to probability of $P(Z \le z)$ (where $Z$ is no greater than one value.) Therefore, apply the identity $P(z_1 \le Z \le z_2) = P(Z \le z_2) - P(Z \le z_1)$ to rewrite $P(-1.61 \le Z \le 0.54)$ as the difference between two probabilities:

$P(-1.61 \le Z \le 0.54) = P(Z \le 0.54) - P(Z \le -1.61)$ .

Look up the z-table for $P(Z \le 0.54)$ and $P(Z \le -1.61)$ :

$P(Z \le 0.54)\approx 0.70540$ .
$P(Z \le -1.61) \approx 0.05370$ .

$\begin{aligned}& P(225 \le X \le 245) \\ &= P\left(\frac{225 - 240}{9.3} \le Z \le \frac{245 - 240}{9.3}\right)\\&\approx P(-1.61 \le Z \le 0.54) \\ &= P(Z \le 0.54) - P(Z \le -1.61)\\ &\approx 0.70540 - 0.05370 \\& \approx 0.65.2 \\ &= 65.2\% \end{aligned}$ .

3 0

4 years ago

Ronnie collects horseshoes and hand grenades and places

lesantik [10]

Answer: 3.5 pounds

Step-by-step explanation:

3 s + 7 h = 32 s = shoes h= hand grenades

6 s + 2 h = 22 Multiply first equation by -2 and add to second equation to get :

-12 h = -42

h = 3.5 pounds

sorry if this was late

8 0

3 years ago