Answer:
the average kinetic energy of its particles increases. When the average kinetic energy of its particles increases, the object's thermal energy increases. Therefore, the thermal energy of an object increases as its temperature increases.
Answer:
[A] Melting
Explanation:
From the giving it means:
H2O(s) - Solid {Ice}
H2O(l) - Liquid {water}
So the equation is:
Liquid ⇒ Solid + Heat
Water ⇒ Ice + Heat
Hence, if you add ice and heat it equal to melting.
Therefore the correct answer is [A] Melting.
<u><em>Kavinsky</em></u>
Answer:
Nitrogen A would be more nucleophilicity (figure 1.)
Explanation:
In the <u>DMAP </u>molecule we will have 2 nitrogens label as "nitrogen A" and "nitrogen B". For nitrogen B we will have more<u> steric hindrance</u> due to the 2 methyls groups and the benzene ring. What will hinder the attack from this nitrogen (nitrogen B) to an <u>electrophile</u>. On the contrary, the attack of nitrogen A could easily occur.
Answer:
138.6 g of C₂HF₃O₂ have 38.9 g of O
Explanation:
Trifluoroacetic acid → C₂HF₃O₂
Molar mass = Mass of C . 2 + Mass of H + Mass of F . 3 + Mass of O .2
Molar mass = 12 . 2 + 1 . 1 + 19 . 3 + 16 . 2 = 114 g /mol
1 mol of C₂HF₃O₂ has:
2 moles of C
1 mol of H
3 moles of F
2 moles of O
If we state the relation in mass by g we say:
114 g of C₂HF₃O₂ have 24g of C, 1 g of H, 57 g of F and 32 g of O
Let's make a rule of three:
32 g of O are contained in 114 g of C₂HF₃O₂
38.9 g of O may be contained in (38.9 . 114) / 32 = 138.6 g
Given :
Mass of caffeine at dangerous level , m = 3 g .
Coffee contains , 21.5 mg/oz OF caffeine .
Mass of cup , 8 oz/cup .
To Find :
Number of cups till dangerous level .
Solution :
Caffeine in a cup of coffee is given by :
Now , number of cups at the dangerous level is given by :
Now , number of cups should be integer .
Therefore , 18 cups of coffee per day is dangerous .