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Ksivusya [100]
3 years ago
13

Which of the following did Mendeleev not believe in because he could not see them?

Chemistry
1 answer:
Zigmanuir [339]3 years ago
6 0

Answer:atoms

Explanation:

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Are inic bonds formed when electrons are equally or unequally shared
lisabon 2012 [21]

The electrons are unequally shared. The electronegative element receives the electrons from the electropositive one.

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3 years ago
think about the statement "there is no new water on earth" write at least 5 sentences describing how there can be no new water o
Vinil7 [7]
Earth contains huge quantities of water in its oceans, lakes, rivers, the atmosphere, and believe it or not, in the rocks of the inner Earth. Over millions of years, much of this water is recycled between the inner Earth, the oceans and rivers, and the atmosphere. This cycling process means that freshwater is constantly made available to Earth's surface where we all live. Our planet is also very efficient at keeping this water. Water, as a vapor in our atmosphere, could potentially escape into space from Earth. But the water doesn't escape because certain regions of the atmosphere are extremely cold. (At an altitude of 15 kilometers, for example, the temperature of the atmosphere is as low as -60° Celsius!) At this frigid temperature, water forms solid crystals that fall back to Earth's surface.
Many people live faraway from freshwater sources. They need to carry their water home.
While our planet as a whole may never run out of water, it's important to remember that clean freshwater is not always available where and when humans need it. In fact, half of the world's freshwater can be found in only six countries. More than a billion people live without enough safe, clean water.
Also, every drop of water that we use continues through the water cycle. Stuff we put down the drain ends up in someone or something else's water. We can help protect the quality of our planet's freshwater by using it more wisely.
8 0
3 years ago
Consider the rate law below.
Serga [27]

C. quadruples the rate

<h3>Further explanation</h3>

Given

The rate law :

R=k[A]²

Required

The rate

Solution

There are several factors that influence reaction kinetics :  

  • 1. Concentration  
  • 2. Surface area  
  • 3. Temperature  
  • 4. Catalyst  
  • 5. Pressure  
  • 6. Stirring  

The rate is proportional to the concentration.

If the concentration increased, the reaction rate will increase

The reaction is second-order overall(The exponent is 2)

The concentration of A is doubled, the reaction rate will increase :

r = k[A]² ⇒ r= k[2A]²⇒r=4k[A]²

<em>The reaction rate will quadruple.</em>

5 0
3 years ago
A mixture of helium, nitrogen, and oxygen has a total pressure of 752 mm Hg. The
NISA [10]

Answer: The partial pressure of oxygen in the mixture is 321 mm Hg

Explanation:

According to Dalton's law, the total pressure is the sum of individual pressures.

p_{total}=p_{He}+p_{N_2}+p_{O_2}

Given : p_{total} = total pressure of gases = 752 mm Hg

p_{He} = partial pressure of Helium = 234 mm Hg

p_{N_2} = partial pressure of nitrogen = 197 mm Hg

p_{O_2} = partial pressure of oxygen = ?

Putting in the values we get:

752mmHg=234mmHg+197mmHg+p_{O_2}

p_{O_2}=321mmHg

The partial pressure of oxygen in the mixture is 321 mm Hg

5 0
3 years ago
How do you test for starch in green plant
Sunny_sXe [5.5K]

Answer:

1,Iodine solution is used to test leaves for the presence of starch. ...

2.After a few minutes, the parts of the leaf that contain starch turn the iodine from brown to blue/black.

3.The leaf on the left is a variegated leaf

Explanation:

4 0
3 years ago
Read 2 more answers
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