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]
3 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]3 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
One day on her walk home from school, Leann noticed some rust on an old car.
skad [1K]

Answer:

Iron and Oxygen

Explanation:

Fe is Iron and O2 is Oxygen

4 0
3 years ago
When the temperature of a reacting mixture increases, the rate of reaction increases. Which statement explains why the rate of r
wlad13 [49]

Answer:

This is one of the factors that affects chemical reactions

Temperature:This is because when the temperature is raised energy in form of heat is supplied to the reacting particles and so the rate of reaction is increased.

3 0
3 years ago
What is the energy change if 84.0 g of calcium oxide (CaO) reacts with excess water in the following reaction?
pochemuha
   The energy change  if 84.0 g   of CaO  react  with  excess  water is  98KJ of heat is released.

calculation
heat  =  number of moles  x  delta H

delta H = - 65.2  Kj/mol

first find the number of  moles  of  CaO reacted

moles = mass/molar mass
the molar mass  of CaO =  40 +  16=  56 g/mol
mass = 84 g
moles therefore = 84 g/56 g/mol =1.5 moles

Heat is therefore =  1.5 moles  x -65.2 = - 97.8 Kj = -98 Kj

  since  sign is  negative  the   energy  is released 

6 0
3 years ago
Each energy sublevel contains __________ number of electrons. For example, sublevel D can hold up to _______ electrons. A. the s
Annette [7]

Answer:

Each energy sublevel contains a different number of electrons. For example, sublevel D can contain up to 10 electrons

Explanation:

The atoms are surrounded by propellers that within each propeller there is a certain number of electrons, these electrons jump from orbit to orbit according to the amount of energy they have. The four levels that make up the electronic cloud that surrounds an atom are: s p d f.

When these electrons change orbit or level they release energy in the form of light, which is known as a photon.

3 0
3 years ago
Both the physical and chemical properites of a substance can change when a substance undergoes a chemical reaction. When a log i
ElenaW [278]
Answer is option C...
6 0
3 years ago
Read 2 more answers
Other questions:
  • Nitrogen dioxide decomposes at 300°C via a second-order process to produce nitrogen monoxide and oxygen according to the followi
    9·1 answer
  • Plz help me with this question, I am stuck
    15·1 answer
  • What is the name for CH 3 CH 2 COCHCH 3 CH(CH 3 ) 2 ?
    13·1 answer
  • What organ is known as the windpipe and the tube takes in air ?
    10·2 answers
  • Plz answer this i will mark brainly like and ratr
    15·1 answer
  • What happens when light waves pass between two materials of different densities?
    8·2 answers
  • What is bond stability??​
    12·2 answers
  • Glycerine is viscous than water?why​
    11·1 answer
  • What is the reason for making fans and wings of aeroplane from plastic?​
    9·1 answer
  • Name some radioactive elements.​
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!