Answer:
25.0g is the mass of sulfur
Explanation:
The sulfur and the oxygen are 50:50. That means there is 1 mole of S per mole of O.
To solve this question we need to convert the mass of O to moles, as moles of O = Moles of S, we can find the moles of S and its mass:
<em>Moles O = Moles S:</em>
12.5g O * (1mol / 16g) = 0.781 moles
<em>Mass S:</em>
0.781 moles * (32g / mol) =
<h3>25.0g is the mass of sulfur</h3>
Answer:
40.02 calories
Explanation:
V = 10 mL = 10g
we know t went <em>up</em> by 4°C, this is our ∆t as it is a change.
Formula that ties it together: Q = mc∆t
where,
Q = energy absorbed by water
m = mass of water
c = specific heat of water (constant)
∆t = temperature change
Q = (10 g) x (4.186 J/g•°C) x (4°C)
Q = 167.44 J
Joules to Calories:
167.44 J x 1 cal/4.184 J = 40.02 calories
(makes sense as in image it is close to the value).
Answer:
128g of Li, will react in this reaction
Explanation:
Before to start working, we need the reaction:
N₂ and Li react, in order to produce Li₃N (lithium nitride)
N₂ + 6Li → 2Li₃N
1 mol of nitrogen reacts with 6 moles of lithium
We convert the mass of N₂ to moles → 86.1 g . 1 mol/ 28g = 3.075 moles
1 mol of N₂ reacts with 6 mol of Li
Therefore, 3.075 moles of N₂ will react with 18.4 moles of Li
We conver the moles to mass → 18.4 mol . 6.94g / 1mol = 128 g
He should transfer the food to another cooler.
This is because for a refrigerator, the temperature should be kept at 40 degrees Fahrenheit in order to slow down the development of the spoilage bacteria that develop in food in the form of color or odor.
A. Heat is released, so the reaction is <u>exothermic</u>.
B. Heat is absorbed, so the reaction is <u>endothermic</u>.
C. Heat is released, so the reaction is <u>exothermic</u>.