Draw the Lewis structure for carbonate

What was the purpose of putting distilled water in the blank cuvette? if your unknown used ethanol as the base solvent, what wou

Margaret [11]

The purpose of using distilled water in the cuvette of the spectrophotometer is to calibrate the instrument. It is generally considered that distilled water shows zero absorbance and 100 % transmittance. So, to zero out the absorbance of compounds other than the analyte being determined, distilled water is used as a blank.

If the unknown being determined is prepared using ethanol as the base solution, the blank used must be ethanol. This is because absorbance if any from the solvent, ethanol must be zeroed out as when the measurement of the actual unknown is being made, the absorbance of the solvent does not interfere.

7 0

2 years ago

The 500kg concrete culvert has a mean radius of 0.5m. part a if the truck has an acceleration of 3m/s2, determine the culvert's

jarptica [38.1K]

Given:

Radius of culvert, r = 0.5 m

Tangential acceleration of the truck, a = 3 m/s2

To determine:

The angular acceleration, α

Explanation:

The tangential acceleration is related to the angular acceleration through the radius as:

a = rα

α = a/r = 3 ms⁻²/0.5 m = 6 s⁻²

Ans: The angular acceleration is 6 s⁻²

6 0

2 years ago

What is an echo? (1 point)

zaharov [31]

Answer:

The reflection of sound waves

Explanation:

An echo is a reflection of sound that bounces of of one thing to another.

4 0

2 years ago

Read 2 more answers

The Ksp can be used to find the concentration of hydroxide ions, and thus determine the pH given a concentration of of aluminum.

Anton [14]

Answer:

3.9.

Explanation:

(Molar mass of 342.15 g/mol).

The first thing to do in this question is to coverts our units. We are given 6.70 lb = 453.592 × 6.70 lb = 3039.0664 g of aluminum sulfate.

2050 gallons of water = 2050 × 3.785 = 7759.25 Litres.

After this we will now look for the Concentration aluminum sulfate using the formula below:

Concentration = number of moles ÷ volume. ------------------------------------(1).

Recall; Number of moles = 3039.0664/ 342.15 = 8.8823 moles. The volume = 2050 gallons = 7759.25 Litres.

Therefore, slotting in the values of of number of moles and volume into the equation (1) above, we have;

Concentration= 8.8823 moles/ 7759.25 Litres. = 0.001145 M.

The next equation we are going to make use of today is that of the solubilty product that is;

Ksp = (Al^3+) (OH^-)^3.

So, we have the ksp = 1.3 × 10^-33 and the value of (Al^3+)= 0.001145 M.

Hence, making (OH^-) the subject of the formula;

(OH^-) = ( 1.3 × 10^-33 / 0.001145)^1/3.

(OH^-) = 8 × 10^-11 M.

Hence, pOH = - log (OH^-)

pOH = - log (8 × 10^-11).

pOH = 10.1

Therefore, the values of pH is; 1

pH + pOH = 14.

pH = 14 - 10.1 = 3.9.

3 0

3 years ago

In an electrolytic cell, the magnitude of the standard cell potential is the:______

melamori03 [73]

Answer:

a. minimum voltage that must be supplied for a redox reaction to occur

c. always equal to Eanode - Ecathode

Explanation:

In an electrolytic cell; The electromotive force(the maximum standard potential difference) of the cell formed by the system is defined as the standard electrode potential of the right handed electrode minus the standard electrode potential of the left hand electrode. (i.e $\mathbf{E^{\theta}_{cell}=E_{anode} - E_{cathode}}$ )

As we all known that the process by which chemical energy is being converted to electrical energy is called the Electrochemical cell. It consists of two half cells , an oxidation half cell reaction and a reduction half-cell reaction.The overall redox reaction results in a flow of electrons in an electric current which is produced by a minimum voltage.

Therefore, option a and c are both correct.

6 0

3 years ago