1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Viktor [21]
3 years ago
9

Tollens’ test, also known as silver-mirror test, is a qualitative laboratory test used to distinguish between an aldehyde and a

ketone. It exploits the fact that aldehydes are readily oxidized (see oxidation),
whereas ketones are not.
Tollens’ test uses a reagent known as Tollens’ reagent,
which is a colorless,
basic,
aqueous solution containing silver ions coordinated to ammonia [Ag(NH3)2+].
It is prepared using a two-step procedure.
Chemistry
1 answer:
Makovka662 [10]3 years ago
3 0

Explanation:

Tollens' reagent is prepared by using two-step process : -

Step 1:

Silver oxide is formed by mixing aqueous silver nitrate with base like sodium hydroxide. The reaction is shown below as:

AgNO_3 + NaOH &\rightarrow AgOH + NHO_3 \nonumber \\ 2AgOH &\rightarrow Ag_2O + H_2O

Step 2

Ammonia solution is drop-wise added until all the silver oxide dissolves to form the reagent. The reaction is shown below as:

Ag_2O + 4NH_3 + H_2O \rightarrow 2Ag(NH_3)_2^+ + 2OH^-

You might be interested in
g To what volume (in mL) should 5.07 mL of an 6.82 M acetic acid solution be diluted in order to obtain a final solution that is
denis-greek [22]

Answer:

The volume of the solution must be increased to 71.429 millimeters by adding 66.359 millimeters of solute to reduce molarity from 6.82 M to 0.49 M.

Explanation:

The molarity is a unit used for solution that is equivalent to the amount of moles of solute per unit volume of solution. That is:

M = \frac{n_{st}}{V_{sol}}

Where:

n_{st} - Amount of moles of solute, measured in moles.

V_{sol} - Volume of the solution, measured in liters.

To reduce the molarity of the solution, more millimeters of solvent should be added. Firstly, the amount of moles of acetic acid inside the 6.82 M solution needs to be determined (M_{o} = 6.82\,M and V_{sol} = 5.07\times 10^{-3}\,L):

n_{st} = M_{o}\cdot V_{sol}

n_{st} = (6.82\,M)\cdot (5.07\times 10^{-3}\,L)

n_{st} = 0.035\,mol

Now, the resulting volume of solution after diluting the acetic acid solution is: (M_{f} = 0.49\,M and n_{st} = 0.035\,mol):

V_{sol} = \frac{n_{st}}{M_{f}}

V_{sol} = \frac{0.035\,mol}{0.49\,M}

V_{sol} = 71.429\times 10^{-3}\,L

V_{sol} = 71.429\,mL (1 L = 1000 mL)

The amount of solvent needed to dilute the solution is:

\Delta V_{sol} = 71.429\times 10^{-3}\,L - 5.07\times 10^{-3}\,L

\Delta V_{sol} = 66.359 \times 10^{-3}\,L

\Delta V_{sol} = 66.359\,mL (1 L = 1000 mL)

The volume of the solution must be increased to 71.429 millimeters by adding 66.359 millimeters of solute to reduce molarity from 6.82 M to 0.49 M.

7 0
3 years ago
Calculate the total mass of the protons and electrons in 19 9F. Use 1.007825 amu as the mass of 11H (mass of a proton and an ele
SVETLANKA909090 [29]

Explanation:

Atomic mass means the sum of total number of protons and neutrons present in an atom.

When an atom is neutral then number of protons equal the number of electrons.

Mass of a proton equals to 1.007276 u, mass of neutron equals to 1.008664 u.

For example, in a ^{19}_{9}F atom there are total 9 protons and number of neutrons is 19 - 9 = 10.

Since, it is a neutral atom so number of electrons will also be 9.

So, total mass will be calculated as follows.

                  Total mass = 9 (mass of electron + mass of proton)

                                      = 9 (1.007825 u)

                                      = 9.07043 u

Therefore, we can conclude that total mass of protons and electrons in ^{19}_{9}F is  9.07043 u.

3 0
3 years ago
14 billion years (roughly the age of the universe) to seconds. (Assume there are 365 days in a year.)
fenix001 [56]

Answer:

                     4.41 × 10¹⁷ Seconds

Explanation:

                   For this problem we will first find out the number of days in 14 billion years.

Remember that 1 billion is equal to 1,000,000,000 or 10⁹. So, 14 billion years will be written as 14,000,000,000 or 1.4 × 10¹⁰ years.

Therefore, In

                           1 year there are  =  365 years

So, In

                  1.4 × 10¹⁰ years  there will be  =  X years,

Solving for X,

                     X =  1.4 × 10¹⁰ years × 365 days / 1 year

                      X =  5.11 × 10¹² days

Secondly, as there are 24 hours per day and each hour has 60 minutes and each minute has 60 seconds, therefore, the number of seconds per day are calculated as,

Number of Sec/day = 24 × 60 × 60

Number of Sec/day = 86400 sec/day

Hence, If,

                               1 day has  =  86400 seconds

then,

                    5.11 × 10¹² days will contain  = X seconds

Solving for X,

                      X =  5.11 × 10¹² days × 86400 sec / 1 day

                     X  =  4.41 × 10¹⁷ Seconds

6 0
3 years ago
200 grams of an organic sample which contains only carbon, hydrogen and oxygen is analyzed and found to contain 97.30grams of ca
Klio2033 [76]
The empirical formula is C2H4O
7 0
3 years ago
Which of the following compounds share electrons? NaCl CO CsF KBr
ArbitrLikvidat [17]
Covalent compounds share with each other, whilst Ionic compounds take from each other. 

Covalent compounds are composed of 2 or more NONMETALS.

So, it would be CO, since the rest of the compounds contain metals in them.
7 0
3 years ago
Other questions:
  • How easily one thing dissolves into another defines what term?
    12·2 answers
  • What problem does the hudson river still face
    11·2 answers
  • Jeremy left his bike outside overnight. When he woke up in the morning, there were water drops on the seat. When he went to ride
    12·1 answer
  • An acid-base titration is a neutralization reaction performed to determine: the concentration of an unknown acid based upon the
    11·1 answer
  • PLEASE ANSWER!!!!!!!endothermic and exothermic reactions lab report
    6·2 answers
  • A student compares the booking point of substances having different intermolecular forces. Which independent variable did the st
    6·1 answer
  • I need help ASAP! I will mark brainiest to whoever is right .
    11·1 answer
  • What elements are nonmetals but aren't halogens or noble gasses?
    5·1 answer
  • A thermometer reads a pressure of 120 kPa at 0 ˚C. What is the temperature when the thermometer reads a pressure of 80 kPa? (Cel
    12·1 answer
  • Can tissue samples be deproteinized for measurement of NAPD/NADPH with 4%w/v sulfosalycilic acid?​
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!