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
Svetradugi [14.3K]
4 years ago
14

Are those correct if not tell me which are wrong I need help with number 21 also

Chemistry
2 answers:
adelina 88 [10]4 years ago
3 0
For 23., you have to find a way to measure your heart rate not increase it. search it up on google.

aniked [119]4 years ago
3 0
For number 21, all you have to do is look at the bar graph and put the answer into a unit rate to make it easier
You might be interested in
The process by which sand is formed from rocks are...
Umnica [9.8K]

Answer:

weathering and erosion

Explanation:

Sand forms when rocks break down from weathering and eroding over thousands and even millions of years. Rocks take time to decompose, especially quartz (silica) and feldspar. Often starting thousands of miles from the ocean, rocks slowly travel down rivers and streams, constantly breaking down along the way.

7 0
3 years ago
Read 2 more answers
Calcium has a cubic closest packed structure (fcc) as a solid. Assuming that calcium has an atomic radius of 197 pm, calculate t
Paha777 [63]

Answer:

1.536 g/cm^3 is the density of solid calcium.

Explanation:

Formula used :  

\rho=\frac{Z\times M}{N_{A}\times a^{3}}

where,

\rho = density

Z = number of atom in unit cell

M = atomic mass

(N_{A}) = Avogadro's number  

a = edge length of unit cell

We have:

r = 197 pm = 197\times 10^{-12} m = 197\times 10^{-12}\times 100 cm

r=197\times 10^{-10} m

a=r\times 2\sqrt{2}

a=197\times 10^{-10} m\times 2\sqrt{2}=557.200\times 10^{-10} cm

M = 40 g/mol

Z = 4

On substituting all the given values , we will get the value of 'a'.

\rho =\frac{4\times 40 g/mol}{6.022\times 10^{23} mol^{-1}\times (557.200\times 10^{-10} cm)^{3}}

\rho =1.536 g/cm^3

1.536 g/cm^3 is the density of solid calcium.

5 0
3 years ago
Scandium 15. Write the nuclear symbol for an ion with a charge of +2,20 protons, and 24
Hoochie [10]
If the element has a charge of +2 it has lost two electrons giving it an overall positive charge making it a cation. In order to find the number of electrons, take the elements atomic number and subtract two since it lost two electrons
8 0
3 years ago
Radiation is a measure of average kinetic energy of particles in an object true or false ​
laila [671]

Answer:false

Explanation:

4 0
3 years ago
Potasyum-40 küçük atom numaralı doğal radyoaktif birkaç element izotopundan biridir ve doğada K izotopları içerisindeki bolluk y
enot [183]

Answer:

6.707 × 10¹⁷

Explanation:

From the information given:

40 ^ K kütlesi = sütteki K kütlesi × 40 ^ K / 100 kütle yüzdesi

nerede;

sütteki K kütlesi = 1.65 mg of K/mL × 225 mL = 371.25  mg of K

∴

40 ^ K kütlesi = 371.25  × 0.012/100

40 ^ K kütlesi = 0,04455 mg = 4.455 × 10⁻⁵ grams

40 ^ K mol sayısı = 40 ^ K kütlesi / molar kütle

= 4.455 × 10⁻⁵/40

= 1.11375 × 10⁻⁶

Son olarak, 40 ^ K = mol × Avogadro sayısı atomları

= 1.11375 × 10⁻⁶  × 6.022 × 10^23

= 6.707 × 10¹⁷

3 0
3 years ago
Other questions:
  • How many independent variables should be in your experimment
    6·1 answer
  • What type of stress is caused by two plates sliding past one another?
    9·1 answer
  • (06.02 LC)
    11·1 answer
  • Which occurs at a larger a wavenumber​
    15·1 answer
  • Which type of mixture can be separated using magnetism?
    6·1 answer
  • Is carbon monoxide or oxygen more ideal gas
    7·2 answers
  • What makes carcinogens so dangerous? A. They can be used to make weapons. B. They are extremely toxic to the environment. C. The
    15·2 answers
  • In a closed system containing three different gases as shown, X2 + Y2 2XY. Choose the TWO things that MUST happen as the volume
    9·1 answer
  • Can someone please help, 20 points <br> Draw 3-ethyl-2,4-dimethyl octanoic acid
    8·1 answer
  • 18. A student recorded the temperature of a chemical reaction to be 85.0°C. At the end of the reaction the
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!