B. the number 3.
there are 2Al's on both sides and 6 Cl's on the right side so to balance it, you multiply Cl2 by 3 to get 6 Cl's.
Answer:
81.59%
Explanation:
First we <u>convert 107.50 g of NH₃ into moles</u>, using its <em>molar mass</em>:
- 107.50 g NH₃ ÷ 17 g/mol = 6.32 mol NH₃
Now we <u>calculate how many moles of NO would have been formed by the complete reaction of 6.32 moles of NH₃</u>:
- 6.32 mol NH₃ *
= 6.32 mol NO
Then we <u>convert 6.32 moles of NO to grams</u>, using its <em>molar mass</em>:
- 6.32 mol NO * 30 g/mol = 189.60 g NO
Finally we <u>calculate the percent yield</u>:
- 154.70 g / 189.60 g * 100% = 81.59%
Answer:
1 and 3.
Explanation:
The entropy measures the randomness of the system, as higher is it, as higher is the entropy. The randomness is associated with the movement and the arrangement of the molecules. Thus, if the molecules are moving faster and are more disorganized, the randomness is greater.
So, the entropy (S) of the phases increases by:
S solid < S liquid < S gases.
1. The substance is going from solid to gas, thus the entropy is increasing.
2. The substance is going from a disorganized way (the molecules of I are disorganized) to an organized way (the molecules join together to form I2), thus the entropy is decreasing.
3. The molecules go from an organized way (the atom are joined together) to a disorganized way, thus the entropy increases.
4. The ions are disorganized and react to form a more organized molecule, thus the entropy decreases.
Iron bending is just a physical change because the iron has only changed shape but there is no new substance. Iron rusting is a chemical change because there is a new substance which is rust.
