Calculate the volume(mo) of 0.50 M NaCl stock solution need to make 100mL of a diluted solution with a concentration of 0.03

Describe how you could use two LB/agar plates, some E. coli, and some ampicillin to determine how E. coli cells are affected by

KiRa [710]

Answer:

For this experiment we are going to take plate 1 as the control plate, so, in it there will be just E. coli in LB/agar; in plate 2, we are going to put E. coli in LB/agar and some ampicillin. Then, we have to wait for the E. coli colonies to form. After a while, the E. coli growth can be compared on both plates and determine if ampicillin affects or not the E. coli colonies.

Explanation:

If the ampicillin affects negatively E. coli colonies, we are going to observe that in plate 1 (control plate) there are E. coli colonies growing, but in plate 2, there is no E. coli colonies or, at least, there is a fewer number of colonies on it. If ampicillin doesn't affect E.coli, plate 1 (control) and plate 2 (ampicillin experiment) are going to be similar in number of colonies.

8 0

3 years ago

9. A student observed the following reaction:

Gelneren [198K]

Answer:

The substance that remained on the filter paper is Al(OH).

Explanation:

Filter paper is the substance that is used in laboratory to separate the solid objects. It doesn't filter aqueous and gaseous products.
So in our experiment the product formed is aluminum hydroxide Al(OH) and sodium chloride (NaCl).
Between two products, sodium chloride is in aqueous form as indicated in the question. So it wont remain in the filter paper.

Hence aluminum hydroxide being only solid product remains on the filter paper.

8 0

3 years ago

Please help me! 45 points each!!

Sveta_85 [38]

Answer:

CH4+ 2Cl2→CH2Cl2+ 2HCl

Explanation:

mass is 132.8`125

as methane and dichlormethane has the same molar ration 1 to 1

mol of ch4 is 1.5625

so 1.5625 times mr of ch2cl2 is 132.8125

8 0

3 years ago

The concentration of calcium in a cell is 0.3%. The concentration of calcium in the surrounding fluid is 0.1%. How could the cel

iragen [17]

Answer:

Primary active transport

Explanation:

In a cell, the movement of molecules like calcium ions (Ca²⁺), <em>to a region having high solute concentration from a region having low solute concentration, through the cell membrane requires metabolic energy</em> and is known as Primary active transport.

It is given that the concentration of calcium in the cell (0.3%) is greater than the concentration of calcium in the fluid surrounding the cell (0.1%). <em><u>So the calcium ions move into the cell and the cell obtains more calcium. </u></em>

<u>Therefore, the cell obtains more calcium by the process of Primary active transport.</u>

4 0

4 years ago

Consider the following reaction: 2 Bi(s) + 3 Cl2(g) → 2 BiCl3(s)

Mandarinka [93]

Taking into account the reaction stoichiometry, 1.119 grams of chlorine gas are required to produce 3.32 grams of bismuth chloride is produced.

<h3>Reaction stoichiometry</h3>

In first place, the balanced reaction is:

2 Bi + 3 Cl₂ → 2 BiCl₃

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

Bi: 2 moles
Cl₂: 3 moles
BiCl₃: 2 moles

The molar mass of the compounds is:

Bi: 209 g/mole
Cl₂: 70.90 g/mole
BiCl₃: 315.45 g/mole

Then, by reaction stoichiometry, the following mass quantities of each compound participate in the reaction:

Bi: 2 moles ×209 g/mole=418 g

Cl₂: 3 moles ×70.90 g/mole= 212.7 g

BiCl₃: 2 moles ×315.45 g/mole= 630.9 g

<h3>Mass of Cl₂ required</h3>

The following rule of three can be applied: If by reaction stoichiometry 630.9 grams of BiCl₃ are formed by 212.7 grams of Cl₂, 3.32 grams of BiCl₃ are formed by how much mass of Cl₂?

$mass of Cl_{2} =\frac{3.32 grams of BiCl_{3}x212.7 grams of Cl_{2} }{630.9 grams of BiCl_{3}}$

<u><em>mass of Cl₂= 1.119 grams</em></u>

Finally, 1.119 grams of chlorine gas are required to produce 3.32 grams of bismuth chloride is produced.

Learn more about the reaction stoichiometry:

<u>brainly.com/question/24741074</u>

<u>brainly.com/question/24653699</u>

5 0

2 years ago