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3 years ago

PLEASE HELP ME!!

Chemistry

1 answer:

ivann1987 [24]3 years ago

6 0

Answer: K and Mg

Explanation:

The first one refers to the atomic radius and increases going down and to the left on the periodic table. K is in between Rb and Na.

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Consider the balanced chemical equation that follows. You are asked to determine how many moles of water you can produce from 4.

matrenka [14]

Explanation:

According to law of conservation of mass, mass of the reactants is equal to the mass of products in a chemical equation. As mass can neither be created nor it can be destroyed but it can be transformed from one form to another.

As it is given that hydrogen and in excess oxygen is reacting that leads to the formation of water. Hence, the chemical reaction equation will be as follows.

$2H_{2}(g) + O_{2}(g) \rightarrow 2H_{2}O(l)$

Since, it is given that 4 mol of hydrogen is reacting with excess of oxygen and gives 2 moles of water.

Hence, number of moles of water produced is calculated as follows.

4 mol of $H_{2} \times \frac{2 mol of H_{2}O}{2 mol of H_{2}}$

= 4 moles of $H_{2}O$

Thus, we can conclude that 4 moles of water you can produce from 4.0 mol of hydrogen and excess oxygen.

3 0

3 years ago

Which describes the state at which products form at the same rate as reactants?

swat32

Chemical equilibrium is the state in which both reactants and products are present in concentrations which have no further tendency to change with time.
Or, we can say that in chemical equilibrium the ratio between the concentration of the reactants and the products is constant.
Chemical equilibrium is a result state when the forward reaction proceeds at the same rate as the reverse reaction.
Different reactions have different equilibrium.

8 0

3 years ago

Read 2 more answers

Molecules can be dissolved? Why?

elixir [45]

Answer:

Dissolving is when the solute breaks up from a larger crystal of molecules into much smaller groups or individual molecules. This break up is caused by coming into contact with the solvent. In the case of salt water, the water molecules break off salt molecules from the larger crystal lattice.

Explanation:

4 0

2 years ago

Read 2 more answers

What is the lower concentration limit (vol%) at which a mixture of ethanol in air can explode?

liubo4ka [24]

Answer:

Lower explosive limit (LEL) of ethanol = 3.3%

Explanation:

In the case of alcohol, ethanol presents certain fire hazards. Its momentary flash point is 55ºF (12.9ºC), while the momentary flash point of gasoline is -45ºF (-42.8ºC), and the E85 mixture ranges between -20ºF and -4ºF (between -28 , 9ºC and -20ºC), and has a wider range of flammability limits than gasoline. For emergency response teams, this implies that during a release of the typical ethanol / gasoline mixture, the fuel can be expected to behave like gasoline: It is heavier than air - as we mentioned earlier - and can produce vapors and form flammable mixtures in the air, under most environmental conditions.

General properties and comparison with other inflambles products:

Flash point momentary Gasoline = -45 ° F

Ethanol = 55 ° F

E 85 = between -20º and -4º F

Flammability limits

Lower explosive limit (LEL) of ethanol = 3.3%

Upper Explosive Limit (UEL) = 19%

Lower explosive limit (LEL) of the mixture E 85 = 1.4%

Upper Explosive Limit (UEL) 85 = 19%

Lower explosive limit (LEL) of gasoline = 1.4%

Upper Explosive Limit (UEL) = 7.6%

They have a wider range than gasoline

4 0

3 years ago

An element with the smallest anionic (negative-ionic) radius would be found on the periodic table in

Advocard [28]

The correct answer for, An element with the smallest anionic (negative-ionic) radius would be found on the periodic table in, is Group 17, Period 2.

5 0

3 years ago