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2 years ago

How many grams of KCIO3 are needed to produce 5.00 of O2 at STP?

1 answer:

6 0

2KClO₃ → 2KCl + 3O₂

mole ratio of KClO₃ to O₂ is 2 : 3

∴ if moles of O₂ = 5 mol

then moles of KClO₃ = $\frac{5 mol * 2}{3}$

= 3.33 mol

Mass of KClO₃ needed = mol of KClO₃ × molar mass of KClO₃

= 3.33 mol × ((39 × 1) + (35.5 × 1) + (16 × 3) g/mol

= 407.93 g

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7. Use the concepts of relative abundance and relative weight to explain why carbon has an atomic mass of 12.011 amu when there

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Extracted from" Atomic weights of the elements 2009 (IUPAC Technical Report)"

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2 years ago

What are properties ?

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Answer:

Explanation:

In logic and philosophy, a property is a characteristic of an object; a red object is said to have the property of redness. The property may be considered a form of object in its own right, able to possess other properties.

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Which of the following is typical of a tropical climate?

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Answer:

Explanation:

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Explain why, when the imidazole ring of histidine is protonated, the double-bonded nitrogen is the nitrogen that accepts the pro

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The important thing to note is the reason why electron react is due to the instability of the electrons. All elements wants to aim the electron configuration of the noble gases. This is the most stable form in which each of the orbitals are sufficiently filled. When it comes to bonding, the order of reactivity is: alkynes > alkenes > alkanes. Alkynes are compounds with triple bonds, alkenes with double bonds and alkanes with single bonds. The single bonds are called saturated hydrocarbons. This is because they have reached stability, so it is quite difficult to react this with reducing or oxidizing agents. Alkynes and alkenes are unsaturated hydrocarbons. They readily react with reducing and oxidizing agents so as to become saturated, as well. The underlying principle for this is that single bonds contain sigma bonds which is the head-on overlapping of electrons. These is the strongest type of covalent bond. Double and triple bonds contain pi bonds which is the side overlapping of electrons orbitals. Hence, these electrons would be easily separated making it more reactive especially during protonation.

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2 years ago

During our phase changes lab, where did we place the thermometer?

IrinaK [193]

The thermometer must be <u>in contact with the ice/water only</u>

Explanation:

In this experiment in the lab, the aim is to measure the specific latent heat of fusion of water.

The specific latent heat of fusion of a substance is the amount of heat energy required to completely melt a certain amount of the substance, mathematically:

$\lambda = \frac{Q}{m}$

where

Q is the heat supplied to the substance

m is the mass of the substance

In this experiment, the aim is to measure the specific latent heat of fusion of water. In order to do that, a mix of ice/water is heated with a certain amount of heat Q, and then it is evaluated the amount of mass m that undergoes melting.

An important precaution that must be taken in this experiment is that the temperature of the water/ice mixture remains constant and equal to the melting point of ice (otherwise, part of the heat supplied to the mixture is used to increase the temperature of the water, resulting in an inaccurate measure of Q). Therefore, a thermometer must be used to check constantly the temperature, and this thermometer must be placed inside the ice/water mixture only (It should not touch the saucepan, whose temperature can be higher).

So, the correct answer is

in contact with the ice/water only

Learn more about specific heat:

brainly.com/question/3032746

brainly.com/question/4759369

#LearnwithBrainly

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