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KengaRu [80]
3 years ago
11

2×21=how many are there​

Chemistry
2 answers:
MArishka [77]3 years ago
8 0

Answer: 42

Explanation:

tensa zangetsu [6.8K]3 years ago
4 0
Multiply 2 * 21

2 * 21
= 42
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Which models of the atom in task 1 are not supported by the results of the hydrogen gas experiment? For each of these models, ex
kramer

Answer:

Thomson  placed two magnets on either side of the tube, and observed that this magnetic field also deflected the cathode ray. The results of these experiments helped Thomson determine the mass-to-charge ratio of the cathode ray particles, which led to a fascinating discovery, minus the mass of each particle was much, much smaller than that of any known atom. Thomson repeated his experiments using different metals as electrode materials, and found that the properties of the cathode ray remained constant no matter what cathode material they originated from. From this evidence, Thomson made the following conclusions:

The cathode ray is composed of negatively-charged particles.

The particles must exist as part of the atom, since the mass of each particle is only ~1/2000 the mass of a hydrogen atom.

These subatomic particles can be found within atoms of all elements.

While controversial at first, Thomson's discoveries were gradually accepted by scientists. Eventually, his cathode ray particles were given a more familiar name: electrons. The discovery of the electron disproved the part of Dalton's atomic theory that assumed atoms were indivisible. In order to account for the existence of the electrons, an entirely new atomic model was needed.

Explanation:

8 0
3 years ago
How much CaCO3 would have to be decomposed to produce 247 g of CaO
vovangra [49]

441 g CaCO₃ would have to be decomposed to produce 247 g of CaO

<h3>Further explanation</h3>

Reaction

Decomposition of CaCO₃

CaCO₃ ⇒ CaO + CO₂

mass CaO = 247 g

mol of CaO(MW=56 g/mol) :

\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{247}{56}\\\\mol=4.41

From equation, mol ratio CaCO₃ : CaO = 1 : 1, so mol CaO :

\tt \dfrac{1}{1}\times 4.41=4.41

mass CaCO₃(MW=100 g/mol) :

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<h3>What is heat transfer?</h3>

Heat transfer is a process that flows the heat from one system to another, and is because of the difference in the temperature of the two objects that are part of the system.

The methods like conduction, convection, and radiation transfer the heat from the surface area to the other object. The heat gets transferred from the area of high to the low temperature.

Therefore, option B. by increasing the surface area the heat transfer increases.

Learn more about heat transfer here:

brainly.com/question/17823456

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Which of the following actions will not increase the rate at which a solid dissolves in
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Answer:

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