All categories

2 years ago

What reagent is used to test for the presence of indole?

1 answer:

7 0

The indole test is a qualitative procedure for determining the ability of bacteria to produce indole by deamination of tryptophan. Using Kovacs tube method, indole combines, in the presence of a tryptophan rich medium, with p-Dimethylaminobenzaldehyde at an acid pH in alcohol to produce a red-violet compound.

You might be interested in

A container is filled with hydrogen gas. It has a volume of 4 liters and a pressure of 2 atm. If the pressure of the container i

Dennis_Churaev [7]

Answer:

1.33 L.

Explanation:

We can use the general law of ideal gas: PV = nRT.

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R is the general gas constant,

T is the temperature of the gas in K.

If n and T are constant, and have different values of P and V:

(P₁V₁) = (P₂V₂)

Knowing that:

V₁ = 4.0 L, P₁ = 2.0 atm,

V₂ = ??? L, P₂ = 6.0 atm.

Applying in the above equation

(P ₁V₁) = (P₂V₂)

∴ V₂ = P ₁V₁/P₂ = (2.0 atm)(4.0 L)/(6.0 atm) = 1.33 L.

4 0

2 years ago

If 6.02×1023 atoms of element Y have a mass of 28.09 g, what is the identity of Y?

Mazyrski [523]

Silicon is the element having a mass of 28.09 g

Explanation:

Silicon is the element having an atomic mass of 28.09 g / mol. So 28.09 g of silicon contains 6.023 $\times$ 10^23 atoms. One mole of each element can produce one mole of compound.

The Atomic weight of an element can be determined by the number of protons and neutrons present in one atom of that element. So atomic weight expressed in grams always contain the same number of atoms( 6.023 $\times$ 10^23).

Avagadro number is the number of atoms of 1 mole of any gas at standard temperature and pressure. It has been determined that 6.023 $\times$ 10^23 atoms of an element are equal to the average atomic mass of that element.

8 0

3 years ago

What happens when we decrease the height of an inclined plane?

Mashutka [201]

Answer:

b is the answer.

Explanation:

5 0

2 years ago

What are the four layers of earth made of?

soldi70 [24.7K]

Answer:

crust, mantle, inner core, outer core

8 0

2 years ago

What is the molarity of a stock solution if 60 mL were used to make 150 ml of a .5M solution?

olga2289 [7]

The molarity of the stock solution is 1.25 M.

Explanation:

We have to find the molarity of the stock solution using the law of volumetric analysis as,

V1M1 = V2M2

V1 = 150 ml

M1 = 0.5 M

V2 = 60 ml

M2 = ?

The above equation can be rearranged to get M2 as,

M2 = $$\frac{V1M1}{V2}$

Plugin the values as,

M2 = $$\frac{150 \times 0.5}{60}$

= 1.25 M

So the molarity of the stock solution is 1.25 M.

4 0

2 years ago