Answer:
25% thorium will left after 50 days.
Explanation:
Half life:
A nuclear half is the time period of radioactive material in which its amount remain halved.
In given question it is stated that the half life thorium-234 is 25 days. Which means after passing the 25 days the amount of thorium must be halved of original amount.
For example,
If the original concentration was 100%, than after 25 days it will be 50%.
After 50 days amount of thorium left:
Number of half life = T (elapsed) / T half life
Number of half life = 50/25
Number of half life = 2
At first half life amount of thorium left = 100/2 = 50
After second half life amount of thorium left = 50/2 = 25
Total amount decayed = 50+25 = 75
Amount left after 50 days = 100-75 = 25
25% thorium will left after 50 days.
Answer:
A. To study the chemical composition of the surface of a planet
Explanation:
Strictly speaking, a spectrometer is any instrument used to view and analyze a range (or a spectrum) of a given characteristic for a substance (for example, a range of mass-to-charge values as in mass spectrometry), or a range of wavelengths as in absorption spectrometry like nuclear magnetic radiation spectroscopy
-hope this helps!
Answer:
trigonal planar
Explanation:
The molecule SO3 is of the type AX3. The molecule is symmetrical and non polar.
There are three regions of electron density in the molecule. This corresponds to a trigonal planar geometry. This means that the three oxygen atoms are arranged at the corners of a triangle. The bond angle is 120 degrees.
first find the atomic weight of CH3 which would be
atomic weight: 12.011 (3×1.008) = 36.32 g/mol
then find the moles in the given mass
36.32 ÷ 45.7 = 0.794
I HOPE I'M NOT WRONG I HAVENT DONE CHEM IN SO LONG
