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
Helen [10]
3 years ago
5

I will give BRAINIEst please!!! help meeee omg

Chemistry
1 answer:
Alexxandr [17]3 years ago
4 0

Answer:

(a)57.48 percent (b) 29.45 percent

Explanation:

copper(II) bromide is 29.45 percent copper and 71.54 percent bromine. so the first element percentage composition is always the percentage composition of the compound.

that goes same with sodium hydroxide. it  is 57.48 percent sodium, 40 percent oxygen, and 2.52 percent hydrogen.

You might be interested in
A mixture of nacl and sucrose (c12h22o11) of combined mass 10.2 g is dissolved in enough water to make up a 250 ml solution. the
Vilka [71]
We use the osmotic pressure to determine the concentration of the solute in the solution. Then, we multiply the volume of the solution to determine the number of moles of solute particles. We need to establish to equations since we have two unknowns, the mass of of each solute. We do as follows:

osmotic pressure = CRT 
<span>C = 7.75 / 0.08205 (296.15) = 0.3189 mol / L</span>
<span>moles of particles = C*V = 0.3189*0.250 =0.0797 mol </span>
<span>0.0797 = moles of sucrose + 2*moles of salt </span>

<span>x + 2y = 0.0797 </span>
<span>and </span>
<span>x(MMsucrose) + y(MMNaCl) = 10.2</span>
<span>342x + 58.5y = 10.2
</span>
<span>solve for x and y
</span>
<span>x = 0.0252 mol sucrose</span>
<span>y = 0.0273 mol NaCl
 </span>
<span>mass Sucrose = 0.0252(342) = 8.6184 g </span>
<span>mass NaCl = 0.0273(58.5) = 1.5971 g </span>
<span>% NaCl = (1.5971 / 10.2)*100 = 15.66%</span>
4 0
3 years ago
Air pressure is lowest in the lungs during whi h of the following points during inspiration or expiration
AlladinOne [14]

Answer:

Inspiration

Explanation:

This question is on application of Boyle's law; <u>pressure is inversely proportional to volume</u>.when we inhale air, the diaphragm and the muscles in the ribs contract thus increasing the volume in the lungs.Increased volume of the lungs cause the pressure to decrease.During exhaling, the diaphragm and muscles in the ribs relax, making the lungs to recoil and reduce in volume to force air out.Pressure in the lungs is increased than that in the environment making air to move out.

4 0
3 years ago
A very old tree limb contains an amount of carbon-14 that is approximately 1/8 of the current atmospheric 14C levels.. Calculate
Tomtit [17]

A.       The radioactive decay equation is N = N0e^{-ln(2)*t/T }

where T is the half-life (5730 years), N0 is the number of atoms at time t = 0 and N is the number at time t.

Rewriting this as:

(N/N0) = e^{-ln(2)*t/T }

Since N = (1/8) N0 and substituting known values:

1/8 = e^{-ln(2)*t/5730}

Taking ln of both sides:

ln(1/8)= -ln(2)*t/5730

t = - 5730 * ln(1/8) / ln (2)

t = 17,190 years

The tree was cut down 17,190 years ago.

B.   N0 = 1,500,000 carbon-14 atoms

Since N = (1/8) N0

N = 187,500 carbon atoms left

3 0
3 years ago
Which ocean surface current travels north along the eastern United States coast? A. Labrador current B. Canaries current C. Gulf
Marina86 [1]
It is answer C
there ya go friend
8 0
3 years ago
Read 2 more answers
Describe the double circulation system of the human body
Alika [10]

Answer:

we have two loops in our body in which blood circulates. One is oxygenated, meaning oxygen rich, and the other is deoxygenated, which means it has little to no oxygen, but a lot of carbon dioxide.

4 0
3 years ago
Other questions:
  • How much heat is required to raise the temperature of 475 grams of solid aluminum from room temperature (295k) to liquid aluminu
    10·1 answer
  • Give the name of the element whose neutral atom tends to have 77 electrons.
    14·1 answer
  • A preliminary untested explanation that tries to explain how or why things happen in the manner observed is a scientific
    6·2 answers
  • What is the justification required to make an arrest?
    6·1 answer
  • A wooden object from the site of an ancient temple has a carbon-14 activity of 10 counts/min compared with a reference piece of
    6·1 answer
  • Why is it important to predict consequences when decision-making?
    10·1 answer
  • Plz help :( plz help me understand :(
    7·1 answer
  • What kind of science experiment idea should I do?
    14·1 answer
  • What are radioactive isotopes?
    7·1 answer
  • In this experiment you used an excess of the BaCl2 solution. How would your results be affected if you did not use an excess of
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!