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
Dmitrij [34]
3 years ago
7

Pure cement can be used as a building material in theory, but the most common application of cement is as a binder that holds ot

her materials together. Concrete is made by adding water to a mixture of cement (the binder) and sand, pebbles, and gravel (the aggregate), which cures to form a solid structure. Which reasons could explain why concrete is used to make structures rather than pure cement?
Chemistry
1 answer:
IrinaVladis [17]3 years ago
7 0
Concrete is used to make structure rather than cement, because

It is cheaper
It produces a more durable structure
It cures more quickly
You might be interested in
The _________________ are either elements or compounds which are present prior to a chemical reaction.
mr Goodwill [35]
Reactants would be the missing word in the sentence because they make up the products in a chemical reaction
3 0
3 years ago
Read 2 more answers
Choose all the answers that apply.
Anni [7]

Answer:

I believe it's the lowest portion of the atmosphere

3 0
3 years ago
What is a stream of charged protons and electrons
Law Incorporation [45]

Answer:

It is called the solar wind thx for asking brainly.com

Explanation:

5 0
3 years ago
The activation energy for proline isomerization of a peptide depends on the identity of the preceding residue and obeys Arrheniu
MAVERICK [17]

Answer:

Activation energy of phenylalanine-proline peptide is 66 kJ/mol.

Explanation:

According to Arrhenius equation-     k=Ae^{\frac{-E_{a}}{RT}}    , where k is rate constant, A is pre-exponential factor, E_{a} is activation energy, R is gas constant and T is temperature in kelvin scale.

As A is identical for both peptide therefore-

                                   \frac{k_{ala-pro}}{k_{phe-pro}}=e^\frac{[E_{a}^{phe-pro}-E_{a}^{ala-pro}]}{RT}

Here \frac{k_{ala-pro}}{k_{phe-pro}}=\frac{0.05}{0.005} , T = 298 K , R = 8.314 J/(mol.K) and E_{a}^{ala-pro}=60kJ/mol

So, \frac{0.05}{0.005}=e^{\frac{[E_{a}^{phe-pro}-(60000J/mol)]}{8.314J.mol^{-1}.K^{-1}\times 298K}}

   \Rightarrow E_{a}^{phe-pro}=65705J/mol=66kJ/mol (rounded off to two significant digit)

So, activation energy of phenylalanine-proline peptide is 66 kJ/mol

7 0
3 years ago
In a fluorine atom, on which energy level are the valence electrons found?
aivan3 [116]

Answer:

second energy level

Explanation:

Valence electrons are those electrons which are present in outer most orbital of the atom.

This can be easily found through the electronic configuration of atom.

Electronic configuration of F:

F₉ = 1s² 2s² 2p⁵

We can see that the valence electrons are present in second energy level of F atom.

There are seven valence electrons of fluorine.

It is called halogens.

Halogens are very reactive these elements can not be found free in nature. Their boiling points also increases down the group which changes their physical states. i.e fluorine is gas while iodine is solid.

Fluorine:

1. it is yellow in color.

2. it is flammable gas.

3. it is highly corrosive.

4. fluorine has pungent smell.

5. its reactions with all other elements are very vigorous except neon, oxygen, krypton and helium.  

6 0
3 years ago
Other questions:
  • Hydrogen produced from a hydrolysis reaction was collected over water and the following data was compiled.
    12·2 answers
  • What is the formula of the chromium(iii) complex that contains two ammonia and four thiocyanate (scn−) ligands?
    14·1 answer
  • For the reaction below, initially the partial pressure of all 3 gases is 1.0atm. . 2NH3(g)--> N2(g) + 3H2(g) K, 0.83 1. When
    7·1 answer
  • The melting point of copper is 1084°C. How does the energy of the particles in a certain amount of liquid copper compare to the
    7·2 answers
  • When moisture in a cloud is heavy enough to fall back into earth, it is called?
    6·1 answer
  • Classify each as a physical or chemical change.
    7·1 answer
  • How many grams of oxygen are there in 45.7 grams of Ba(NO2),?
    10·1 answer
  • Please help me this is a big grade please
    12·1 answer
  • The cl-cl bond will react more readily, because it has a
    12·1 answer
  • Someone pls help me I will make you brain
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!