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
otez555 [7]
2 years ago
10

Why do we use acid during the detection of halogens​

Chemistry
1 answer:
ohaa [14]2 years ago
8 0

Answer:

Nitric acid decomposes sodium cyanide and sodium halide. else, they precipitate in test and misguide the result. Therefore, dilute nitric acid is added before testing halogens to expel all the gases if evolved.

You might be interested in
2. Which of the following does not have a nucleus? a. prokaryotes b. eukaryotes c. prokaryotes and eukaryotes ​
qwelly [4]

Answer:

Erythrocytes

Erythrocytes do not contain a nucleus. This would make answer choice "A" correct. Erythrocytes are red blood cells and these cells differ from the other cells of the body because of the absence of the nucleus. All the other cells noted have nuclei.

Explanation:

Have A Wonderful Day !!

3 0
3 years ago
Read 2 more answers
A gas mixture contains 10.0 mole% H2O (v) and 90.0 mole % N2. The gas temperature and absolute pressure at the start of each of
Rainbow [258]

Answer: (a). T = 38.2 °C     (b). V = 1.3392 cm³     (c). ii and iii  

Explanation:

this is quite easy to solve, i will give a step by step analysis to solving this problem.

(a). from the question we have that;

the Mole fraction of Nitrogen, yи₂ = 0.1

Also the Mole fraction of Water, yн₂o = 0.1

We know that the vapor pressure is equal to the partial pressure because the vapor tends to condense at due point.

ρн₂o = ṗн₂o

      = yн₂oP = 0.1 × 500 mmHg = 50 mmHg

from using Antoine equation, we apply the equation

logρн₂o = A - B/C+T

T = B/(A - logρн₂o) - C

  = 1730.63 / (8.07131 - log 50mmHg) - 223.426

T = 38.2 °C

We have that the temperature for the first drop of liquid form is 38.2 °C

(b). We have to calculate the total moles of gas mixture in a 30 litre flask;

   n  = PV/RT  

   n = [500(mmHG) × 30L] / [62.36(mmHGL/mol K) × 323.15K] = 0.744 mol

Moles of H₂O(v) is 0.1(0.744) = 0.0744 mol

Moles of N₂ is 0.9(0.744) = 0.6696 mol

we have that the moles of water condensed is 0.0744 mol i.e the water vapor  in the flask is condensed

Vн₂o = 0.0744 × 18 / 1 (g/cm³)

Vн₂o = 1.3392 cm³

Therefore, the  volume of the liquid water is 1.3392 cm³

(3). (ii) and (iii)

The absolute pressure of the gas and The partial pressure of water in the gas would change if the barometric pressure drops.

cheers i hope this helps!!!!

4 0
3 years ago
The mole is defined as the amount of a substance containing the same number of particles as exactly 12 g of C-12. The amu is def
Pavlova-9 [17]

Answer:

Because it wouldn't make any sense

Explanation:

First of all, I think it's important to highlight the definition of isotope.

Isotope (Wikipedia): Variants of a particular chemical element <u>which differ in neutron number</u>...

This means that two isotopes are the same element but have different net mass per atom, due to the different number of neutrons.

Therefore, it's important to make the definition on the same isotope so that the proportion is equal. If the definition would be made on different isotopes, the proportion wouldn't have any sense. Let me be clear with this example:

mass in grams of a C-12 atom = 1.9944235 × 10 ^ -23 g  --> this is the mass of a single C atom.

By definition --> 1 mol of anything = 6.02 x 10 ^ 23 particles of anything

Therefore, we know how much a single C atom weights. How many grams do you think that 6.02 x 10 ^ 23 atoms of C (i.e a mol of C) could weight??

1 single C atom ----------------------------- 1.9944235 × 10 ^ -23 g

6.02 x 10 ^ 23 atoms of C   ------------ <u>12.006 g  !!</u>

These 12 g is the same quantity than above! Therefore, 1 mol of C weights 12 g. If the definition were made with 13 g of C-13 (the other C isotope), these numbers will not be the same --> There would be a contradiction.

Regarding the second question, we need to search Ne-20 atomic mass in grams -->  3,3509177 × 10 ^ -23 g

Hence, if we follow the same rule, the amu would be 1/12 of Ne-20.

[ 3,3509177 × 10 ^ -23 g ] / 12 = 2.79 ^ -24 g

3 0
3 years ago
What is the atomic mass of one mole of H? _______g/mol
Nikolay [14]
The answer is 1.008g/mol
8 0
4 years ago
Calculate the energy (in kJ) required to heat 10.1 g of liquid water from 55 oC to 100 oC and change it to steam at 100 oC. The
Maksim231197 [3]

Answer:

           \large\boxed{\large\boxed{24.6kJ}}

Explanation:

<u>1. Energy to heat the liquid water from 55ºC to 100ºC</u>

     Q=m\times C\times \Delta T

  • m = 10.1g
  • C = 4.18g/JºC
  • ΔT = 100ºC - 55ºC = 45ºC

     Q=10.1g\times 4.18J/g\ºC\times 45\ºC=1,899.81J

<u>2. Energy to change the liquid to steam at 100ºC</u>

      L=\lambda \times n

  • λ = 40.6kJ/mol
  • n = 10.1g / 18.015g/mol = 0.5606mol

      L=40.6kJ/mol\times 0.5604mol=22.76214kJ=22,762.14J

<u>3. Total energy</u>

       1,899.81J+22,762.14J=24,661.95J\approx24,662J\approx24.6kJ

7 0
4 years ago
Other questions:
  • This is simple I am just confused
    14·1 answer
  • Which example does not involve knowledge of chemistry?
    13·2 answers
  • Which statement is true of the motion of the ball?
    11·1 answer
  • Which solution below yields the lowest final concentration of a sodium hydroxide solution prepared by diluting 50.00 mL of conce
    8·1 answer
  • How many molecules are present in this sample <br><br> 0.423 mol co
    15·1 answer
  • how many grams of silver medal could be recovered from a reaction of 50 g silver nitrate and copper metal
    14·1 answer
  • Which water feature is often associated with condensation?
    7·2 answers
  • How does the ocean<br> currents affect weather?
    8·1 answer
  • Scientist repeats an experiment and gets a<br> different result. What should the scientist do next
    10·1 answer
  • Which particle diagram represents a mixture of three substances
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!