How many moles of iron are made from 15 moles of iron (iii) oxide

1) A 
"arrow" should be "yields." 
The coefficients are mole ratios. So every 4 moles of NH3, or ammonia, produce 6 moles of H2O, water. 

(12 mol NH3)(6 mol H2O/4 mol NH3) = 18 mol H2O produced 

2) C 
Again, use the coefficients to form mole ratios and solve. See #1. 

3) C 
4)C 
5) C 
Moles, clearly. It's another constant you MUST MEMORIZE, like Avogadro's number. (Shame on you if you don't know what Avogadro's number means!) At STP (273.15 K and 1 atm), one mole of any ideal gas is 22.4 L. 

6) C 
Same thing as #1-4, except with a twist: molar masses. You calculate the molar masses using the periodic table. 

Molar mass of H = 1.008 g/mol 
Molar mass of O = 16.00 g/mol 
Molar mass of H2O = 2(1.008 g/mol) + 16.00 g/mol) = 18.016 g/mol 
Molar mass of O2 = 2(16.00 g/mol) = 32.00 g/mol 

Divide the mass of water by the molar mass to find the number of moles of water. Use mole ratios to find the number of moles of O2 consumed. Then, multiply by the molar mass to find mass of O2. Tada! 

7) 
8) 
9) 
10) 
11) 
12) See number 13 
13) True 
14) False; doesn't tell a thing about the speed of the reaction, how spontaneous it is, or at what temperature or pressure it must take place.

1) A 
"arrow" should be "yields." 
The coefficients are mole ratios. So every 4 moles of NH3, or ammonia, produce 6 moles of H2O, water. 

(12 mol NH3)(6 mol H2O/4 mol NH3) = 18 mol H2O produced 

2) C 
Again, use the coefficients to form mole ratios and solve. See #1. 

3) C 
4)C 
5) C 
Moles, clearly. It's another constant you MUST MEMORIZE, like Avogadro's number. (Shame on you if you don't know what Avogadro's number means!) At STP (273.15 K and 1 atm), one mole of any ideal gas is 22.4 L. 

6) C 
Same thing as #1-4, except with a twist: molar masses. You calculate the molar masses using the periodic table. 

Molar mass of H = 1.008 g/mol 
Molar mass of O = 16.00 g/mol 
Molar mass of H2O = 2(1.008 g/mol) + 16.00 g/mol) = 18.016 g/mol 
Molar mass of O2 = 2(16.00 g/mol) = 32.00 g/mol 

Divide the mass of water by the molar mass to find the number of moles of water. Use mole ratios to find the number of moles of O2 consumed. Then, multiply by the molar mass to find mass of O2. Tada! 

7) 
8) 
9) 
10) 
11) 
12) See number 13 
13) True 
14) False; doesn't tell a thing about the speed of the reaction, how spontaneous it is, or at what temperature or pressure it must take place.

Answer: chalcogens.
Explanation: Strontium is an alkaline earth metal, it always exhibits a degree of oxidation in its compounds +2.
Chalcogens are a group of 6 chemical elements (oxygen O, sulfur S, selenium se, tellurium te, polonium Po) that have an oxidation state of -2 => Chalcogens will combine with strontium in a ratio of 1:1.

Answer:

A

Step-by-step explanation:

The input force is 50 N. But it will not create not any change. No mechanical advantage is observed.

Answer:

52.6 gram

Step-by-step explanation:

It is clear by the equation 2(27+3×35.5)= 267 gm of AlCl3 reacts with 6× 80 = 480 gm of Br2 . So 29.2 gm reacts = 480× 29.2/267= 52.6 gm

15 moles.Explanation:Hello,In this case, the undergoing chemical reaction is:Clearly, since carbon and oxygen are in a 1:1 molar ratio, 15 moles of carbon will completely react with 15 moles of oxygen, therefore 15 moles of oxygen remain as leftovers. In such a way, since carbon and carbon dioxide are also in a 1:1 molar ratio, the theoretical yield of carbon dioxide is 15 moles based on the stoichiometry:Best regards.

Answer: 7.8125 g
Explanation: Given:
Original amount (N₀) = 500 g
Number of half-lives (n) = 9612/1602 = 6
Amount remaining (N) = ?
N = 1/2ⁿ × N₀
N = 1/2^6 × 500
N = 0.015625 × 500
N = 7.8125 g