Answer:
2.74 M
Explanation:
Given data:
Mass of sodium chloride = 80.0 g
Volume of water = 500.0 mL
Molarity of solution = ?
Solution:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
Now we will convert the mL into L.
500.0 mL× 1 L /1000 mL = 0.5 L
In next step we will calculate the number of moles of sodium chloride.
Number of moles = mass/molar mass
Number of moles = 80.0 g/ 58.4 g/mol
Number of moles = 1.37 mol
Molarity:
M = 1.37 mol/ 0.5 L
M = 2.74 M
Answer:
The main function of the cell membrane is to protect the cell from the outer environment.
Answer:
Option B. A
Explanation:
From the question given above, the following data were obtained:
C(s) + 2H₂ (g) —> CH₄ (g). ΔH = –74.9 kJ
From the reaction above, we can see that the enthalpy change (ΔH) is negative (i.e –74.9 KJ) which implies that the heat content of the reactants is greater than the heat content of the products. Thus, the reaction is exothermic reaction.
For an exothermic reaction, the energy profile diagram is drawn in such a way that the heat content of reactants is higher than the heat content of products because the enthalpy change
(ΔH) is always negative.
Thus, diagram A (i.e option B) gives the correct answer to the question.
<u>Answer:</u> The average speed of the runner is 6.618 miles/hr
<u>Explanation:</u>
Average speed is defined as the ratio of total distance traveled to the total time taken.
To calculate the average speed of the runner, we use the equation:
We are given:
Distance traveled = 4339 ft
Time taken = 7.45 mins
Putting values in above equation, we get:
To convert the speed into miles per hour, we use the conversion factors:
1 mile = 5280 ft
1 hr = 60 mins
Converting the speed into miles per hour, we get:
Hence, the average speed of the runner is 6.618 miles/hr
Answer:
The correct option is A
Explanation:
An independent variable is <u>a variable that is intentionally altered (directly or indirectly) and is not dependent on another variable</u> in the course of an experiment. Unlike the independent variable, the dependent variable depends or is presumed to depend on the altered independent variables.
From the explanation above, it can be deduced that the concentration of the catalase is the independent variable as it was intentionally altered (by using different concentrations) in the course of the experiment. The amount of oxygen given off is the dependent variable here
