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
Akimi4 [234]
3 years ago
9

Please help ! What’s the correct answer ?

Chemistry
1 answer:
Ber [7]3 years ago
4 0
To code for proteins
You might be interested in
What happens to electrons in the photoelectric effect?
mafiozo [28]

The correct answer is B. on Apex!

8 0
2 years ago
Read 2 more answers
Active and inactive volcano in philipines?
finlep [7]

355 volcanoes in the Philippines are inactive.

24 volcanoes are active

3 0
3 years ago
__is a term that refers to the amount of space that a substance or an object takes up
Anni [7]
Volume perhaps ?

Hope this helps !
3 0
3 years ago
The unit cell for cr2o3 has hexagonal symmetry with lattice parameters a = 0.4961 nm and c = 1.360 nm. If the density of this ma
IRINA_888 [86]

To calculate the packing factor, first calculate the area and volume of unit cell.

Area is calculated as:

A=6R^{2}\sqrt{3}

Here, R is radius and is related to a as follows:

R=\frac{a}{2}

Putting the value in expression for area,

A=6(\frac{a}{2})^{2}\sqrt{3}=1.5a^{2}\sqrt{3}

The value of a is 0.4961 nm

Since, 1 nm=10^{-7}cm

Thus, 0.4961 nm=4.961\times 10^{-8} cm

Putting the value,

Area=1.5(4.961\times 10^{-8}cm)^{2}\sqrt{3}=6.39\times 10^{-15}cm^{2}

Now, volume can be calculated as follows:

V=Area\times c

The value of c is 1.360 nm or 1.360\times 10^{-7} cm

Putting the value,

V=(6.39\times 10^{-15}cm^{2})\times (1.360\times 10^{-7} cm)=8.7\times 10^{-22}cm^{3}

now, number of atom in unit cell can be calculated by using the following formula:

n=\frac{\rho N_{A}V_{c}}{A}

Here, A is atomic mass of Cr_{2}O_{3} is 151.99 g/mol.

Putting all the values,

n=\frac{(5.22 g/cm^{3})(6.023\times 10^{23} mol^{-1})(8.7\times 10^{-22}cm^{3})}{(151.99 g/mol)}\approx 18

Thus, there will be 18 Cr_{2}O_{3} units in 1 unit cell.

Since, there are 2 Cr atoms and 3 oxygen atoms thus, units of chromium and oxygen will be 2×18=36 and 3×18=54 respectively.

The atomic radii of Cr^{3+} and O^{2-} is 62 pm and 140 pm respectively.

Converting them into cm:

1 pm=10^{-10}cm

Thus,

r_{Cr^{3+}}=6.2\times 10^{-9}cm

and,

r_{O^{2-}}=1.4\times 10^{-8}cm

Volume of sphere will be sum of volume of total number of cations and anions thus,

V_{S}=V_{Cr^{3+}}+V_{O^{2-}}

Since, volume of sphere is V=\frac{4}{3}\pi r^{3},

V_{S}=36\left ( \frac{4}{3}\pi (r_{Cr^{3+})^{3}} \right )+54\left ( \frac{4}{3}\pi (r_{O^{2-})^{3}} \right )

Putting the values,

V_{S}=36\left ( \frac{4}{3}(3.14) (6.2\times 10^{-9} cm)^{3}} \right )+54\left ( \frac{4}{3}(3.14) (1.4\times 10^{-8} cm)^{3}} \right )=6.6\times 10^{-22}\times 10^{-8}cm^{3}

The atomic packing factor is ratio of volume of sphere and volume of crystal, thus,

packing factor=\frac{V_{S}}{V_{C}}=\frac{6.6\times 10^{-22}cm^{3}}{8.7\times 10^{-22}cm^{3}}=0.758

Thus, atomic packing factor is 0.758.

6 0
3 years ago
Read 2 more answers
When do replicated chromosomes are aligned in the center
Art [367]

Answer:

<u>During Metaphase</u>

<u></u>

Explanation:

During Metaphase the cell chromosome align themselves in the middle of the cell.This occur due to a cellular process called "Tug of War".

The chromosome which have been replicated and joined at the central point  called centromere are called sister chromatids

Prior to metaphase , Kinetochore type of protein are formed around the centromere. Long protein filament called kinetochore are extended from poles to other end of the cell attached to kinetochore.

Therse is important checkpoint in the middle of mitosis called<u> metaphase.</u>

At this point cell ensure that , it is ready to divide or not.

Once the cell ensure that everything is ready to divide. Only after then , yhe cell enters the fourth phase called <u>anaphase.</u>

7 0
2 years ago
Other questions:
  • Calculate the molar solubility of fe(oh)2 in pure water. (the value of ksp for fe(oh)2 is 4.87×10−17.)
    7·1 answer
  • Is it possible to decrease resistance of the wire without changing the material it's made out of?
    13·1 answer
  • Consider the biochemical pathway: A + E1 –&gt; B + E2 –&gt; C (Note that A, B, and C are molecules in the pathway, E1 is enzyme
    12·1 answer
  • The acidic substance in vinegar is acetic acid, HC2H3O2. When 4.00 g of a certain vinegar sample was titrated with 0.200 M NaOH,
    8·1 answer
  • Which color has the longest wavelength?
    8·1 answer
  • A frying pan needs a Teflon coating of 1.00 mm in thickness to cover an area of 36.0 square inches. How many ounces of Teflon ar
    11·1 answer
  • When blood moves from an atrium to a ventricle, it must pass through a __________
    7·2 answers
  • Propane is used as a fuel for camp stoves. It undergoes combustion to form carbon dioxide and water.
    6·1 answer
  • Taking your foot off of the gas pedal when you see a police car which of the Newton’s law
    6·1 answer
  • How many moles of water can be made when 48 moles of HNO3 are consumed?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!