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
alina1380 [7]
2 years ago
6

Read the descriptions below of two substances and an experiment on each. Decide whether the result of the experiment tells you t

he substance is a pure substance or a mixture, if you can.
Sample A is of a coarse grey powder with a faint unpleasant smell. of the powder is put into a funnel lined with a sheet of thick paper. Distilled water is poured slowly over the powder. Most of the powder disappears, but of a gritty black sand-like material is left on the surface of the paper. Pouring more water over the black material doesn't change how much of it there is.

Sample B is a solid yellow cube with a total mass of 50.0 g. The cube is put into a beaker filled with 250. mL of water. The cube collapses into a small pile of orange powder at the bottom of the beaker. When this powder is filtered out, dried and weighed, it has a total mass of 29.9 g. If the experiment is repeated with 500. mL of water, the powder that's left over has a mass of 10.0 g.
Chemistry
1 answer:
Lelu [443]2 years ago
8 0

Answer:

Sample A - mixture

Sample B- Mixture

Explanation:

Looking at sample A, we can see that as water was poured over sample A, the sample was separated into its components as the powder disappeared leaving behind a gritty black sand-like material on the surface of the paper. A separation of the mixture has taken place.

In sample B, we can clearly see that it is a mixture because the amount of solid recovered is much less than the total mass of the solid put into the beaker. The sample must have been separated into its components.

You might be interested in
A 7.12 L cylinder contains 1.21 mol of gas A and 4.94 mol of gas B, at a temperature of 28.1 °C. Calculate the partial pressure
GenaCL600 [577]

Answer:

P_A=4.20atm\\\\P_B=17.1atm

Explanation:

Hello!

In this case, since the equation for the ideal gas is:

PV=nRT

For each gas, given the total volume, temperature (28.1+273.15=301.25K) and moles, we can easily compute the partial pressure as shown below:

P_A=\frac{n_ART}{V} =\frac{1.21mol*0.082\frac{atm*L}{mol*K}*301.25K}{7.12L} \\\\P_A=4.20atm\\\\P_B=\frac{n_BRT}{V} =\frac{4.94mol*0.082\frac{atm*L}{mol*K}*301.25K}{7.12L} \\\\P_B=17.1atm

Best regards!

8 0
3 years ago
What element is represented by [Rn]7s1?
lara [203]

Answer:

Radon

Explanation:

4 0
3 years ago
Explain the relationship between plate tectonics and volcanos
ad-work [718]

Answer:

Plates sliding past each other cause friction and heat. Subducting plates melt into the mantle, and diverging plates create new crust material. Subducting plates, where one tectonic plate is being driven under another, are associated with volcanoes and earthquakes.

Explanation:

7 0
3 years ago
Use the data given below to construct a Born-Haber cycle to determine the heat of formation of KCl. Δ H°(kJ) K(s) → K(g) 89 K(g)
AURORKA [14]

Explanation:

The net equation will be as follows.

          K(s) + Cl_{2}(g) \rightarrow KCl(s)

So, we are required to find \Delta H_{formation} for this reaction.

Therefore, steps involved for the above process are as follows.

Step 1:  Convert K from solid state to gaseous state

          K(s) \rightarrow K(g),    \Delta H_{1} = 89 kJ

Step 2:  Ionization of gaseous K

           K(g) \rightarrow K^{+}(g) + e^{-},    H_{2} = 418 KJ

Step 3:  Dissociation of Cl_{2} gas into chlorine atom .

            \frac{1}{2} Cl_{2}(g) \rightarrow Cl(g),   \Delta H_{3} = \frac{244}{2} = 122 KJ

Step 4: Iozination of chlorine atom.

              Cl(g) + e^{-} \rightarro Cl^{-}(g),      H_{4} = -349 KJ

Step 5:  Add K^{+} ion and Cl^{-} ion formed above to get KCl .

              K^{+}(g) + Cl^{-}(g) \rightarrow KCl(s),   H_{5} = -717 KJ

Now, using Born-Haber cycle, value of enthalpy of the formation is calculated as follows.

      \Delta H_{f} = \DeltaH_{1} + \Delta H_{2} + \Delta H_{3} + \Delta H_{4} + \Delta H_{5}

                  = 89 + 418 + 122 - 349 - 717

                  = - 437 KJ/mol

Thus, we can conclude that the heat of formation of KCl is - 437 KJ/mol.

5 0
3 years ago
If I had a mixture of salt, sand, and iron filings I could separate the mixture by …
liubo4ka [24]
Okay to separate this mixture you will have to first use a magnet because the magnet will attract the iron filings out of the sand then you will remain with the sand and salt.

Next step is to add water to the sand and salt mixture the salt will dissolve in the water and the sand will not forming a heterogeneous mixture.Then using the method of filtration you can separate the sand from  the salt solution leaving the salt solution

 To separate the salt from the water use the method of evaporation this will enable you to get back the salt 

In the end you should beable to have the sand,salt and iron filings separate.

Hope this was helpful to you.

Happy New Years !!! May your year be prosperous 






3 0
3 years ago
Other questions:
  • When using 100ml or 50ml graduated cylinder to what decimal place can your volume be estimated?<br>​
    9·1 answer
  • Which is the number of valence electrons in cadmium (Cd)?
    10·2 answers
  • Another name for resting position in science ?
    14·1 answer
  • Which of the following properties decreases from left to right across a period? *
    13·1 answer
  • Question 8
    11·1 answer
  • During which phase of the moon do neap tides occur
    7·2 answers
  • 3. 2 HCl (aq)
    6·1 answer
  • What is the best definition of the enthalpy change Hr
    11·1 answer
  • If another student joins the game and stands behind the two students
    12·1 answer
  • What is the number of protons in the nucleus of the atom
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!