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Artyom0805 [142]
2 years ago
6

WHICH ELEMENT HAS ATOMIC NUMBER 78?

Chemistry
1 answer:
inn [45]2 years ago
3 0

Answer:

platinum

Explanation:

it's atomic number is 78

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The Ostwald process is used commercially to produce nitric acid, which is, in turn, used in many modern chemical processes. In t
Sloan [31]

Answer:

Mass =  42.8g

Explanation:

4 NH 3 ( g ) + 5 O 2 ( g ) ⟶ 4 NO ( g ) + 6 H 2 O ( g )

Observe that every 4 mole of ammonia requires 5 moles of oxygen to obtain 4 moles of Nitrogen oxide and 6 moles of water.

Step 1: Determine the balanced chemical equation for the chemical reaction.

The balanced chemical equation is already given.

Step 2: Convert all given information into moles (through the use of molar mass as a conversion factor).

Ammonia = 63.4g × 1mol / 17.031 g = 3.7226mol

Oxygen = 63.4g × 1mol / 32g = 1.9813mol

Step 3: Calculate the mole ratio from the given information. Compare the calculated ratio to the actual ratio.

If all of the 1.9831 moles of oxygen were to be used up, there would need to be 1.9831 × 4 / 5 or 1.5865 moles of Ammonia. We have 3.72226 moles of ammonia - Far excess. Because there is an excess of Ammonia, the Oxygen amount is used to calculate the amount of the products in the reaction.

Step 4: Use the amount of limiting reactant to calculate the amount of H2O produced.

5 moles of O2  = 6 moles of H2O

1.9831 moles = x

x = (1.9831 * 6 ) / 5

x = 2.37972 moles

Mass of H2O = Molar mass * Molar mass

Mass = 2.7972 * 18

Mass =  42.8g

6 0
3 years ago
Which compound is an isomer of propanoic acid (CH3CH2COOH)?
arlik [135]

Answer:

D) HCOOCH2CH3

Explanation:

An isomer of a compound is defined as a chemical substances with the same formula (That is, same atoms) but in different structures.

For propanoic acid, there are <em>3 atoms of C, 6 atoms of H and 2 atoms of oxygen.</em>

A) CH2CHCOOH . Here you have 3 atoms of C but 4 atoms of H. That means this compound is not an isomer.

B) CH3CH2CH2COOH . Here, there are 4 atoms of C. Thus, is not an isomer.

C) CH3CH(OH)CH2OH. This structure has 3 atoms of C, but 8 atoms of H. Thus, is not an isomer.

D) HCOOCH2CH3. Here, there are 3 atoms of C, 6 atoms of H and 2 atoms of O. Thus, this structure <em>is an isomer of propanoic acid.</em>

5 0
2 years ago
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The reaction for the decomposition of ammonia (NH3) can be written as shown. If a student starts with 21.7 g of ammonia, how man
Eddi Din [679]
3.88 grams will be released I believe
3 0
3 years ago
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How many molecules are in 3.2 mol of ammonia,NH3
EastWind [94]
Here we are talking about ammonia which is a molecule. Now 1 mole of ammonia also contains 6.022<span> * 10^</span>23 molecules<span> of ammonia. In one molecule of ammonia,we have 1 nitrogen atom and 3 hydrogen atom.</span>
5 0
3 years ago
The Concrete that surrounds a swimming pool takes less time to heat up than the water in the pool. Why
yuradex [85]

Answer:

The Concrete has a lower specific heat.

Explanation:

4 0
2 years ago
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