Answer:
The experimental plan is to measure the values of the dependent variable, which is the temperature of the pizza after it is cooled in each of the heat (temperature) environments, which is the dependent variable, for a given equal period of time, which is the control
Explanation:
The given parameters are;
The temperature of the pizza = 400°F
The temperature of the freezer = 0°F
The temperature of the refrigerator = 40°F
The temperature of the countertop = 78°F
Given that the independent variable = The heat to which the hot pizza is subjected
The dependent variable = The temperature to which the pizza cools down
The experiment plan includes;
1) Place the pizza which is at 400°F in each of the different heat environment, which are, the freezer, the fridge, and the counter top, for the same period of time and record the final temperature of the pizza
2) The option that gives the lowest final temperature within the same time frame is the option that will let the pizza cool down fastest.
<span>d)Electrons need specific amounts of energy to "jump" off an atom and be emitted.</span>
Answer:
2, strong acid
Explanation:
Data obtained from the question. This includes:
[H+] = 0.01 M
pH =?
pH of a solution can be obtained by using the following formula:
pH = –Log [H+]
pH = –Log 0.01
pH = 2
The pH of a solution ranging between 0 and 6 is declared to be an acid solution. The smaller the pH value, the stronger the acid.
Since the pH of the above solution is 2, it means the solution is a strong acid.
Explanation:
Given problem:
Find the molar mass of:
SO₃ and C₁₀H₈
Solution:
The molar mass of a compound is the mass in grams of one mole of the substance.
To solve this, we are going to add the individual atomic masses of the elements in the compound;
Atomic mass;
S = 32g/mol; O = 16g/mol; C = 12g/mol and H = 1g/mol
For SO₃;
= 32 + 3(16)
= 32 + 48
= 80g/mol
For C₁₀H₈
= 10(12) + 8(1)
= 120 + 8
= 128g/mol
Answer:
3.64g
Explanation:
Given parameters:
Mass of NH₃ = 18.1g
Mass of Cu₂O = 90.4g
Unknown:
Limiting reactant = ?
Mass of N₂ formed = ?
Solution:
The reaction equation is given as:
Cu₂O + 2NH₃ → 6Cu + N₂ + 3H₂O
The limiting reactant is the one in short supply in the reaction. Let us find the number of moles of the given species;
Number of moles =
Molar mass of Cu₂O = 2(63.6) + 16 = 143.2g/mol
Molar mass of NH₃ = 14 + 3(1) = 17g/mol
Number of moles of Cu₂O =
= 0.13moles
Number of moles of NH₃ =
= 5.32moles
From this reaction;
1 mole of Cu₂O combines with 2 mole of NH₃
So 0.13moles of Cu₂O will combine with 0.13 x 2 mole of NH₃
= 0.26moles of NH₃
Therefore, Cu₂O is the limiting reactant. Ammonia is in excess;
Mass of N₂;
Mass = number of moles x molar mass
1 mole of Cu₂O will produce 1 mole of N₂
0.13 mole of Cu₂O will produce 0.13 mole of N₂
Mass = 0.13 x (2 x 14) = 3.64g