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
kotykmax [81]
3 years ago
5

20. Which of the following are pure substances?

Chemistry
1 answer:
Juliette [100K]3 years ago
3 0
The answer is III and V
You might be interested in
Reaction of (r)-2-chloro-4-methylhexane with excess nai in acetone gives racemic 2-iodo-4-methylhexane. what is the explanation
saveliy_v [14]

I believe this question has the following five choices to choose from:

 

>an SN2 reaction has occurred with inversion of configuration

>racemization followed by an S N 2 attack

>an SN1 reaction has taken over resulting in inversion of configuration

>an SN1 reaction has occurred due to carbocation formation

>an SN1 reaction followed by an S N 2 “backside” attack

 

 

The correct answer is:

an SN1 reaction has occurred due to carbocation formation 

4 0
3 years ago
If a school uses 1200 gallons/day. How many liters/sec is this?
Naddik [55]

Answer:

0.05257 L/s

Explanation:

Step 1: Given data

The school uses 1200 gallons/day

Step 2: Convert "gal/day" to "L/day"

We will use the conversion factor 1 gal = 3.785 L.

1200 gal/day × (3.785L/gal) = 4542 L/day

Step 3: Convert "L/day" to "L/s"

We will use the following conversion factors:

  • 1 day = 24 h
  • 1 h = 3600 s

4542 L/day × (1 day/24 h) × (1 h/3600 s) = 0.05257 L/s

5 0
3 years ago
What is the Tychonic System?
ziro4ka [17]
<span>Tychonic System is a model of the Solar system that embraces all the benefits of Copernican and Ptolemaic systems, forming the most accurate one. This system was introduced by Tycho Brahe in16th century, and it looks like this:  the Earth is placed at the center of the universe, the Sun, Moon and the stars revolve around the Earth, and the other planets, in their turn, revolve around the Sun. </span>
5 0
3 years ago
What is not represented by a balanced chemical equation?
astraxan [27]

Answer is: 4) The same subscripts are on each side of the equation.

For example, balanced chemical reaction:

2Mg + O₂ → 2MgO.

1) The same number of atoms is on each side of the equation: two magnesium atoms and two oxgen atoms.

2) The formulas for all substances are correct: in magnesium oxide (MgO), magnesium has oxidation number +2 and oxygen -2, so formula is good, because compound must be neutral.

3) The same mass is represented on each side of the equation: because there is same number of atoms, the mass is the same.

4) The same subscripts are on each side of the equation: oxygen does not have same subscripts.

5 0
3 years ago
A consequence of "yo-yo dieting is that A. cholesterol levels will increase. B. A person will develop allergies to certain foods
Tju [1.3M]

the correct option is C.

Weight cycling refers to the repeated process of loosing and gaining weight. When weight cycling is caused by dieting it is called yo-yo dieting. Yo-yo dieting has many potential negative effects and one of them is increases in body fat percentage. Other negative consequences include: diabetes, fatty liver, high blood pressure, etc.

5 0
2 years ago
Read 2 more answers
Other questions:
  • Convert 34.59cm3 to cubic inches (in3) given that 1 inch = 2.54cm
    8·1 answer
  • How many elements compose the majority of rock-forming minerals?
    7·1 answer
  • What is the chemical name and formula of a compound that has one carbon atom and four chlorine atoms?
    12·2 answers
  • Which of the following compounds would be named with a name that ends in -yne?
    9·2 answers
  • Which of the following is the correct formula for sulfuric acid?
    8·2 answers
  • Typically, a dichotomous key moves from the _______ to the specific traits when helping us to identify organisms.
    8·2 answers
  • What codes for the characteristics of an organism?
    5·1 answer
  • A cylinder measuring 9.7 cm wide and 12. cm high is filled with gas. The piston is pushed down with a steady force measured to b
    11·1 answer
  • Which of the data sets qualitative data?
    8·2 answers
  • Why did Tim conclude that all matter is mostly made of empty space?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!