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Delicious77 [7]
2 years ago
6

Which substance has a standard enthalpy of formation of zero?.

Chemistry
1 answer:
joja [24]2 years ago
7 0

Answer: In its natural condition, a pure element

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Calculate the number of grams of CO that can react with 0.400 kg of Fe2O3.
aleksandr82 [10.1K]

Answer:

mass of CO = 210.42 g

mass in three significant figures = 210. g

Explanation:

Given data:

mass of Fe2O3 = 0.400 Kg

mass of CO= ?

Solution:

chemical equation:

Fe2O3 + 3CO → 2Fe + 3CO2

Now we will calculate the molar mass of  Fe2O3 and CO.

Molar mass of  Fe2O3 = (55.845 × 2) + (16 × 3) = 159.69 g/mol

Molar mass of CO = 12+ 16 = 28 g/mol

now we will convert the kg of Fe2O3 in g.

mass of Fe2O3 = 0.400 kg × 1000 = 400 g

number of moles of Fe2O3  = 400 g/ 159.69 g/mol = 2.505 mol

mass of CO = moles of Fe2O3 × 3( molar mass of CO)

mass of CO = 2.505 mol × 84 g/mol

mass of CO = 210.42 g

mass in three significant figures = 210. g

5 0
4 years ago
Read 2 more answers
Help please 20points
lions [1.4K]

Answer:

D

Explanation:

D is the answer because this is the only one having to do with genetics. Fox's genetics changed because it's environment changed.

6 0
3 years ago
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how many moles of iron will be produced from 6.20 moles of carbon monoxide reacting with excess iron (III) oxide (FeO3) to produ
Gelneren [198K]

0.20 moles of iron will be formed in the reaction.

Explanation:

The balanced chemical equation for the reaction between iron (iii) oxide and carbon monoxide to form Fe is to be known first.

the balanced reaction is :

Fe2O3 + 3CO⇒ 2 Fe + 3 CO2

so from the data given the number of moles of carbon monoxide can be known:

3 moles of CO reacted with Fe2O3 to form 2 moles of iron in the reaction.

Number of moles of CO is 6.20 moles

11.6 gm of iron is formed

so the number of moles of iron formed is calculated as

n = mass of iron ÷ atomic weight of iron

  = 11.6 ÷ 55.84

  = 0.20 moles of iron will be formed when 11.6 gram of iron is produced.

5 0
3 years ago
The brain tells his stomach intestines and liver want to be active and want to rest. Messages to and from the brain decide when
Nana76 [90]

Answer:

Nervous System I believe

Explanation:

5 0
3 years ago
What are the 4 factors that makes a good fuel
Paha777 [63]

Hi Jojo


The 4 factors that makes a good fuel are

1) It should be cheap

2)It should not burn too fast or too slowly

3) It should be easily available

4) It should have a high calorific value


I hope that's help !

8 0
3 years ago
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