What color is this maroon or red

Solution A is yellow when alizarin yellow is added and blue when thymol

olga2289 [7]

Answer:

D. 6.3 x 10-5 mol/L NaOH

Explanation:

Alizarin yellow is an indicator that is yellow when pH < 10.1. In the same way, thymol blue is blue when pH > 9

That means the pH of the solution is between 9 - 10.1

Any acid as HCl could have a pH of these.

The solution of 3.2x10⁻⁴M NaOH has a pH of:

pOH = -log[OH-] = 3.49

pH = 14-pOH = 10.51. The pH of the solution is not 10.5

Now, the solution of 6.3x10⁻⁵M NaOH has a pH:

pOH = -log[OH-] = 4.2

pH = 14-pOH = 9.8

The pH of the solution could be 9.8. Right option is:

4 0

3 years ago

4. What is the dependent variable in the statement below?

Naddik [55]

A. Amount of sleep, since it depends on how much coffee she drinks

4 0

4 years ago

Read 2 more answers

There are two steps in the usual industrial preparation of acrylic acid, the immediate precursor of several useful plastics. In

kodGreya [7K]

<u>Answer:</u> The net chemical equation for the production of acrylic acid is given below.

<u>Explanation:</u>

We are given two intermediate equations:

<u>Equation 1:</u> $CaC_2(s)+2H_2O(g)\rightarrow C_2H_2(g)+Ca(OH)_2(s)$

<u>Equation 2:</u> $6C_2H_2(g)+3CO_2(g)+4H_2O(g)\rightarrow 5CH_2CHCO_2H(g)$

To get the net chemical equation for the formation of acrylic acid from calcium carbide, carbon dioxide and water, we multiply the first equation by a factor of '6'.

The equation becomes:

<u>Equation 1:</u> $6C_2H_2(g)+6Ca(OH)_2(s)$

<u>Equation 2:</u> $6C_2H_2(g)+3CO_2(g)+4H_2O(g)\rightarrow 5CH_2CHCO_2H(g)$

Net chemical equation now becomes:

$6CaC_2(s)+16H_2O(g)+3CO_2(g)\rightarrow 5CH_2CHCO_2H(g)+Ca(OH)_2(s)$

Hence, the net chemical equation for the production of acrylic acid is given above.

3 0

3 years ago

Sarah measures out 151 grams of SO2. How many moles is this? Express your answer to three significant figures.

Anna11 [10]

Answer:

$\boxed {\boxed {\sf 2.36 \ mol \ SO_2}}$

Explanation:

We are asked to convert grams to moles. We will use the molar mass and dimensional analysis to perform this conversion.

<h3>1. Molar Mass</h3>

The molar mass is the mass of 1 mole of a substance. These values are found on the Periodic Table because they are equivalent to the atomic masses, but the units are grams per mole instead.

We are given a mass of sulfur dioxide (SO₂). Look up the molar masses of the individual elements.

Sulfur (S): 32.07 g/mol
Oxygen (O): 15.999 g/mol

Notice that the formula of the compound contains a subscript. The subscript after O means there are 2 moles of oxygen in 1 mole of sulfur dioxide. We must multiply oxygen's molar mass before adding sulfur's.

O₂: 15.999 * 2 = 31.998 g/mol
SO₂= 32.07 + 31.998 = 64.068 g/mol

<h3>2. Convert Grams to Moles </h3>

Now we will use dimensional analysis to convert grams to moles. From the molar mass, we know there are 64.068 grams of sulfur dioxide per mole, so we can set up a ratio.

$\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}$

We are converting 151 grams to moles, so we multiply by this value.

$151 \ g \ SO_2 *\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}$

Flip the ratio so the units of grams of sulfur dioxide cancel.

$151 \ g \ SO_2 *\frac {1 \ mol \ SO_2}{64.068 \ g \ SO_2}$

$151 *\frac {1 \ mol \ SO_2}{64.068 }$

$\frac {151}{64.068 } \ mol \ SO_2$

$2.356870825 \ mol \ SO_2$

<h3>3. Round </h3>

The original measurement of grams (151) has 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place. The 6 in the thousandth place tells us to round the 5 in the hundredth up to a 6.

$2.36 \ mol \ SO_2$

151 grams of sulfur dioxide is approximately <u>2.36 moles of sulfur dioxide.</u>

8 0

3 years ago

What is Dark Matter? someone pls tell me. grand reward

Nutka1998 [239]

Answer:

Dark matter is nonluminous material that is postulated to exist in space and that could any of Several form including weakly interacting particles.

Explanation:

dark matter is basically composed of particles that do not absorb, reflect or emit light, so they can't be detected by observing electromagnetic radiation.

5 0

2 years ago