Answer:
0.3 mol
Explanation:
Assuming HCl is in excess and Zn is the limiting reagent,
from the balanced equation, we can see the mole ratio of Zn:H2 = 1:1,
which means, each mole of zinc reacted gives 1 mole of H2.
So, if 0.30 mol Zn is added, the no. of moles of H2 produced will also be 0.3 mol, since the ratio is 1:1.
The k is the proportionality constant of the reaction. Graphically, this is the slope of the graph. Since the graph is linear, then there is only 1 value of k. To calculate this, choose two random points in the line. Suppose we use (0.15,10) and (0.30,20), calculate for the slope.
Slope = k = (10 - 20)/(0.15 - 0.30) = 66.67 mL CO₂/g CaCO₃
Q = mxcxdelta t
or
231 = 10.8x6.55x Delta t
Delta t = 3.265 degrees celcius
I think it's the Pentium up
115
<span>he's in the 15th column, 7th period </span><span />
Answer:
Explanation:
When water changes from ice (solid) to water (liquid), it is melting or fusion. Therefore, we can use the following formula to find energy:
where <em>q</em> is the energy, <em>m </em>is the mass, and <em>Hf</em> is the heat of fusion.
1. Define Values
The mass is 150 grams. The heat of fusion for water is 334 Joules per gram.
2. Calculate Energy
Substitute the values into the formula.
Multiply. Note that the grams (g) will cancel each other out and leave Joules as our units.
3. Convert Units
We found the answer in joules, but the question asks for kilojoules, so we must convert.
There are 1000 Joules in 1 kilojoule. Therefore, we can divide the joules calculated by 1000.
<u>50.1 kilojoules </u>are needed to change 150 grams of ice to water.