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
Law Incorporation [45]
2 years ago
6

Which of the following materials fall in the category of a ‘‘pure substance’’?

Chemistry
1 answer:
pishuonlain [190]2 years ago
6 0

Answer:

1) <em>Ice, iron, calcium oxide and mercury</em> are <u>pure substances since they contain particles of only one kind of matter.</u>

2) <em>In contrast, milk, hydrochloric acid</em> (hydrogen chloride gas dissolved in water), brick and air cannot be called <u>pure substances because they consists of particles of more than one kind of matter.</u>

You might be interested in
Something that dissolves in liquid <br><br>solven<br> solute<br> solution ​
Feliz [49]

Answer: solute

Explanation:

6 0
3 years ago
Why does an exothermic reaction need activation energy?
andrey2020 [161]

Answer:

Activation energy is needed so reactants can move together, overcome forces of repulsion, and to begin breaking bonds.

Explanation:

6 0
3 years ago
Five million gallons per day (MGD) of wastewater, with a concentration of 10.0 mg/L of a conservative pollutant, is released int
hjlf

Answer:

a) The concentration in ppm (mg/L) is 5.3 downstream the release point.

b) Per day pass 137.6 pounds of pollutant.  

Explanation:

The first step is to convert Million Gallons per Day (MGD) to Liters per day (L/d). In that sense, it is possible to calculate with data given previously in the problem.  

Million Gallons per day 1 MGD = 3785411.8 litre/day = 3785411.8 L/d

F_1 = 5 MGD (\frac{3785411.8 L/d}{1MGD} ) = 18927059 L/d\\F_2 =10 MGD (\frac{3785411.8 L/d}{1MGD} )= 37854118 L/d

We have one flow of wastewater released into a stream.  

First flow is F1 =5 MGD with a concentration of C1 =10.0 mg/L.

Second flow is F2 =10 MGD with a concentration of C2 =3.0 mg/L.  

After both of them are mixed, the final concentration will be between 3.0 and 10.0 mg/L. To calculate the final concentration, we can calculate the mass of pollutant in total, adding first and Second flow pollutant, and dividing in total flow. Total flow is the sum of first and second flow. It is shown in the following expression:  

C_f = \frac{F1*C1 +F2*C2}{F1 +F2}

Replacing every value in L/d and mg/L

C_f = \frac{18927059 L/d*10.0 mg/L +37854118 L/d*10.0 mg/L}{18927059 L/d +37854118 L/d}\\C_f = \frac{302832944 mg/d}{56781177 L/d} \\C_f = 5.3 mg/L

a) So, the concentration just downstream of the release point will be 5.3 mg/L it means 5.3 ppm.

Finally, we have to calculate the pounds of substance per day (Mp).  

We have the total flow F3 = F1 + F2 and the final concentration C_f. It is required to calculate per day, let's take a time of t = 1 day.  

F3 = F2 +F1 = 56781177 L/d \\M_p = F3 * t * C_f\\M_p = 56781177 \frac{L}{d} * 1 d * 5.3 \frac{mg}{L}\\M_p = 302832944 mg

After that, mg are converted to pounds.  

M_p = 302832944 mg (\frac{1g}{1000 mg} ) (\frac{1Kg}{1000 g} ) (\frac{2.2 lb}{1 Kg} )\\M_p = 137.6 lb

b) A total of 137.6 pounds pass a given spot downstream per day.

4 0
3 years ago
A time during a child's life span when he/she is most sensitive to environmental influences or stimulation than at other times d
aivan3 [116]
I think during toddler years, I used to be sooo paranoid during that time because I used to think about robbery, etc.
7 0
2 years ago
What are your main fears about this class (if any)?​
netineya [11]
This is based on your personal opinion lol but ig you can say public speaking
8 0
3 years ago
Read 2 more answers
Other questions:
  • What radioactive emissions is the most penetrating?
    13·1 answer
  • How should scientist respond when new evidence that challenges current is presented?
    14·1 answer
  • The thikness of an eye lash is 15 mm how much this will be in meters ? write it in scientific Notation.
    14·1 answer
  • Help please? :)
    10·2 answers
  • Which has a larger atomic radius, F or F-?
    14·2 answers
  • Which type of reaction involves one element replacing another element in a compound
    11·2 answers
  • What is the 25 element in chemistry
    5·1 answer
  • Which of the following pairs of elements could NOT react to
    12·2 answers
  • Describe the motion of a person NOT wearing a seat belt if the car stops suddenly
    12·1 answer
  • 3. 6 th grade Question
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!