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
Zigmanuir [339]
3 years ago
9

If a 7% saline solution and a 4% saline solution are mixed to make 500 milliliters of a 5% saline solution, how much of each sol

ution, to the nearest milliliter, is needed?
A. 167 milliliters of 7% solution and 333 milliliters of 4% solution
B. 110 milliliters of the 10% solution and 210 milliliters of 4% solution
C. 155 milliliters of the 10% solution and 300 milliliters of 4% solution
D. 170 milliliters of the 10% solution and 340 milliliters of 4% solution
Chemistry
1 answer:
GenaCL600 [577]3 years ago
4 0
The correct answer is A. <span>167 milliliters of 7% solution and 333 milliliters of 4% solution and here is how: 
</span><span>If x is the number of milliliters of the 7% saline solution and y is the number of milliliters of the 4% saline solution then add up to 500 milliliters total, so x + y = 500. 
</span>and if we do
x + y = 500 
<span>x = 500 - y </span>
<span>0.07x + 0.04y = 25 (substitute 500 - y for x) </span>
<span>0.07(500 - y) + 0.04y = 25 </span>
<span>35 - 0.07y + 0.04y = 25 </span>
<span>-0.03y + 35 = 25 </span>
<span>-0.03y = -10 </span>
<span>y = 333.333... </span>
<span>y = about 333 </span>
<span>x = 500 - y = 500 - 333 = 167 
</span>Then you know why the answer is A. 
You might be interested in
A. property is a characteristic of a pure substance that can be observed without changing the substance into some thing else
wlad13 [49]
The answer is physical property.

Physical properties are the properties that does not require the substance changing into another substance, which is, chemical change. Physical properties are usually observable and measurable, such as melting points, density, odor, color etc. These does not require a chemical reaction to happen.

The opposite of physical property is chemical property, which is how the substance changes to another. Such as how sodium reacts with water to make sodium hydroxide and hydrogen.
7 0
3 years ago
What does nature versus nurture mean
amm1812

Answer:

Nature versus nurture is a long-standing debate in biology about the balance between two competing factors which determine fate: environment and genetics. The alliterative expression "nature and nurture"

3 0
2 years ago
Read 2 more answers
Use an example how natural selection can lead to evolution
Eddi Din [679]
Natural selection leads to evolutionary change when individuals with certain characteristics have a greater survival or reproductive rate than other individuals in a population and pass on these inheritable genetic characteristics to their offspring.
3 0
3 years ago
Determine if each compound shown is soluble or insoluble.
Iteru [2.4K]

Answer:

Ths CvevGH jgt

Explanation:

4 0
3 years ago
Which layer is the YOUNGEST?
Elina [12.6K]
3 is the youngest later
4 0
4 years ago
Other questions:
  • The compound FeCI3 is made of
    12·1 answer
  • In any nuclear reaction, nuclei are transformed in some way.<br> TRUE<br> FALSE
    9·2 answers
  • Ain ionic is a bond between
    12·2 answers
  • A chemistry student weighs out 0.154 g of chloroacetic acid (HCH2CICO2) into a 250. mL volumetric flask and dilutes to the mark
    9·1 answer
  • Which statement best summarizes this part of kafka's the metamorphosis?
    5·2 answers
  • What are water and carbon dioxide in the cellular respiration reaction
    10·1 answer
  • State general trend for metal properties as you go left to right across a period
    8·1 answer
  • A 3L sample of an ideal gas at 178 K has a pressure of 0.3 atm. Assuming that the volume is constant, what is the approximate pr
    15·1 answer
  • Which arrow or arrows represent reactions that demonstrate a conservation of mass and energy? Explain your answer.
    14·2 answers
  • Which statement best describes a chemical change?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!