Answer:
126g
Explanation:
Data obtained from the question include:
Mole of Fe = 2.5moles
Molar Mass of Fe = 56g/mol
Mass of Fe =?
Number of mole = Mass/Molar Mass
Mass = number of mole x molar Mass
Mass of Fe = 2.25 x 56
Mass of Fe = 126g
Therefore, the mass in 2.25mol of Fe is 126g
Half life is the time taken by a radioactive isotope to decay by half its original mass.
The original mass is 200 g
Time taken is 60 hours
Final mass is 25 g
Therefore;
Final mass = Original mass × (1/2)^n; where n is the number of half lives.
25 = 200 (1/2)^n
1/8 = (1/2)^n
n = 3
Three half lives = 60 hours
1 half lives = 20 hours
Therefore; the half life of the radioactive nucleus is 20 hours
Answer:
A
Explanation:
because on the first alphabet they've been specific of the weather partaking in the area
Answer:
1.3 L
Explanation:
The volume of a rectangular cube can be calculated using the following formula:
Volume (L) = length (cm) x width (cm) x height (cm)
Keep in mind that 1 L = 1,000 cm³.
Before you can plug the values into the equation, you need to make sure they all have the same unit. Since the length is in meters (m), you need to first convert it to centimeters.
1 meter = 100 cm
0.159 m 100 cm
--------------- x ---------------- = 15.9 cm
1 m
Now, you can solve for the volume. To find the answer is the unit liters, you need to divide the volume by 1,000.
Volume = l x w x h
Volume = 15.9 cm x 10.5 cm x 7.7 cm
Volume = 1,285.5 cm³
Volume = 1.2855 L ------> Volume = 1.3 L
My best try would be d an element