Answer:
- <u>Dependent variable</u>
Explanation:
In a controlled <em>experiment </em>there will be one independent variable, one dependent variable, and some controlled or constant parameters.
The target of the expermiment is to tes how the dependent variable changes with the independent variable.
So, the scientist will change (manipulate) the independent variable and measure the dependent vabiales.
Here, the temperature will be manipulated (within a range), so this is the independent variable; the height of the cake is the variable whose behavior wants to be determined, so this is the dependent variable. Controlled variables or constants may include the mixture, the size of the pan, the time of cooking, the oven, among others.
K:
m=155g
M=39g/mol
n = 155g / 39g/mol ≈ 3,97mol
KNO₃:
m=122g
M=101g/mol
n = 122g/101g/mol = 1,21mol
2K + 10KNO₃ ⇒ 6K₂O + N₂
2mol : 10mol
3,97mol : 1,21mol
limiting reagent
KNO₃ is limiting reagent
To solve this question, you must use the formula: q=mc(change in temperature), where q is heat, m is mass, C is specific heat and temperature change is temperature change. The specific heat for ice is 2.1kJ/Kg x K (given). The change in temperature is 15 degrees Celsius (which you should change to kelvins so you can cancel out units), or 273 + 15 = 288K. The mass is 150 grams, which is 0.15 kg. Now, we can solve for q, heat. We will do this by substituting variables into the formula. After simplifying and cancelling out units, the answer we get is: 90.72kJ.
