Answer:
There will be produced 1.71 moles of B which contain 1.03×10²⁴ molecules
Explanation:
The example reaction is:
2A → 3B
2 moles of A produce 3 moles of B
If we have the mass of A, we convert it to moles and then, we make the rule of three: 29.2 g / 25.6g/mol = 1.14 moles
Therefore 2 moles of A produce 3 moles of B
1.14 moles of A will produce (1.14 . 3) / 2 = 1.71 moles of B are produced
Now we can determine, the number of molecules
1 mol has NA molecules (6.02×10²³)
1.71 moles have (1.71 . NA) = 1.03×10²⁴ molecules
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.
Answer:
A mixture is a physical combination of substances thus it only requires physical processes to separate. However, a compound is chemically combined and can only be separated by chemical processes. Therefore, it is much harder to separate a compound than a mixture.
Answer:
Option A.
2Na + 2H2O —> 2NaOH + H2
Explanation:
To know which option is correct, we shall do a head count of the number of atoms present on both side to see which of them is balanced. This is illustrated below below:
For Option A:
2Na + 2H2O —> 2NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 2 Na
4 H >>>>>>>>>>>> 4 H
2 O >>>>>>>>>>>> 2 O
Thus, the above equation is balanced.
For Option B:
2Na + 2H2O —> NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 1 Na
4 H >>>>>>>>>>>> 3 H
2 O >>>>>>>>>>>> 1 O
Thus, the above equation is not balanced.
For Option C:
2Na + H2O —> 2NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 2 Na
2 H >>>>>>>>>>>> 4 H
1 O >>>>>>>>>>>> 2 O
Thus, the above equation is not balanced.
For Option D:
Na + 2H2O —> NaOH + 2H2
Reactant >>>>>>> Product
1 Na >>>>>>>>>>> 1 Na
4 H >>>>>>>>>>>> 5 H
2 O >>>>>>>>>>>> 1 O
Thus, the above equation is not balanced.
From the illustrations made above, only option A is balanced.
