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3 years ago

An electrical company charges 15 p per unit of energy (kWh).

Chemistry

1 answer:

Alja [10]3 years ago

4 0

Answer:

180 p

Explanation:

Energy refers to the capacity of doing work.

Amount charged by an electrical company = 15 p per unit of energy (kWh)

As 1 W = 1000 kW,

$500W=\frac{500}{1000}kW=0.5\,kW$

Also, 1 day = 24 hours.

Cost of running a 500 W freezer = 0.5 kW freezer for 1 hour = $15\times 0.5=7.5\,p$

Therefore,

cost of running a 0.5 kW freezer for a day ( 24 hours ) = $7.5\times 24=180\,p$

Amount charged by an electrical company = 15 p per unit of energy (kWh)

As 1 W = 1000 kW,

$500W=\frac{500}{1000}kW=0.5\,kW$

Also, 1 day = 24 hours.

Cost of running a 500 W freezer = 0.5 kW freezer for 1 hour = $15\times 0.5=7.5\,p$

Therefore,

cost of running a 0.5 kW freezer for a day ( 24 hours ) = $7.5\times 24=180\,p$

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2Fe(s) +3H2SO4(aq) →Fe2(SO4)3(aq) +3H2(g)When 10.3 g of iron are reacted with 14.8 moles of sulfuric acid, what is the percent y

Elden [556K]

Answer:

1040%

Explanation:

To solve this question we must convert the mass of Iron to moles in order to find limiting reactant. With limiting reactant we can find the theoretical moles of hydrogen and theoretical mass:

Percent yield = Actual yield (5.40g) / Theoretical yield * 100

<em>Moles Fe -Molar mass: 55.845g/mol-:</em>

10.3g * (1mol / 55.845g) = 0.184 moles of Fe will react.

For a complete reaction of these moles there are necessaries:

0.184 moles Fe* ( 3 mol H2SO4 / 2 mol Fe) = 0.277 moles H2SO4.

As there are 14.8 moles of the acid, <em>Fe is limiting reasctant.</em>

The moles of H2 produced are:

0.184 moles Fe* ( 3 mol H2 / 2 mol Fe) = 0.277 moles H2

The mass is:

0.277 moles H2 * (2.016g/mol) = 0.558g H2

Percent yield is:

5.40g / 0.558g * 100 = 1040%

It is possible the experiment wasn't performed correctly

7 0

3 years ago

Process by which plants, algae, and many types of bacteria use sunlight, water, and carbon dioxide to make food and oxygen

Katena32 [7]

Answer: Photosynthesis

Explanation:

<em>The process of photosynthesis</em> is used to help make food for plants. The inputs are sunlight, water (H2O), and carbon dioxide (CO2). Then the outputs are glucose (C6H12O6) which is food, and oxygen (O2) is released.

I hope this helps :)

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3 years ago

A chemical equation does not give information about what

Lana71 [14]

A chemical equation does not give information about the following:

It usually does not give the "state of the substances". There are three states: Solid(s), liquid(q) and gas(vap).
The chemical equation does not show whether it is complete or incomplete.
The "speed of the reaction" is not mentioned.
The "concentration of the substance" whether it is diluted or concentrated is not mentioned.
The "rate of the reaction", temperature, catalyst, pressure etc is not mentioned. These can be mentioned "above or below the arrow".

8 0

3 years ago

Write your name on a piece of paper with a water soluble marker and place the slime on top of it and remove very quickly before

creativ13 [48]

Uh i did this because it made me curious... i may have done it wrong nothing happened

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3 years ago

18. Which statement about photosynthesis is FALSE?

joja [24]

<h3>your query : </h3>

Which statement about photosynthesis is FALSE?

Answer:

b. Oxygen is needed as a reactant to produce

glucose is the incorrect statement here

Explanation:

plants uses simple raw materials to prepare their food , which includes water ( H2O ) and Carbon dioxide ( CO2 ).

and traps sunlight by Green pigments known as chlorophyll and stores these energy in bonds of glucose molecules

so ,

after this reaction glucose and oxygen is formed as products

● hence we conclude that Oxygen is not needed as a reactant to produce glucose , oxygen is the bi product formed during photosynthesis.

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3 years ago