Answer:
37S
Explanation:
Radioactivity is the spontaneous emission of particles and / or electromagnetic radiation by unstable atomic nuclei leading to their disintegration.
We have two main types of radioactivity: radioactive decay and artificial transmutation.
In radioactive decay ( natural radioactivity ), a naturally occurring radioactive element like Uranium-238 disintegrates or decays into more stable isotopes with the emission of particles and/or radiation.
23892U = 23490Th + 42He
Artificial transmutation is the collision of two particles where one particle captures the other used to bombard it. There is subsequent production of isotopes similar or different from the bombarded particle. Neutrons, alpha particles ( helium nucleus ), electrons, protons can be used to bombard elements.
147N + 42He = 178O + 11P
For the above question which is artificial transmutation, the reaction equation is
4018Ar + 10n = 3716S + 42He
So, the neutron capture by Argon-40 will produce a radioisotope Sulphur-37 with the emission of an alpha particle.
Answer:
magnetite
Explanation:
proportion of iron in haematite = 3.5/5 x 100% = 70%
proportion of iron in magnetite = 7.2/10 x 100% = 72%
Answer:
Diluted concentration is 0.5M
Explanation:
Let's solve this with rules of three, although there is a formula to see it easier
In 1000 mL (1L), we have 2 moles of NaOH
In 250 mL we must have (250 . 2) / 1000 = 0.5 moles of NaOH
These moles will be also in 1 L of the final volume of the diluted solution
More easy:
1 L of solution has 0.5 moles of NaOH
Then, molarity is 0.5 M
The formula is: Concentrated M . Conc. volume = Diluted M . Diluted volume
2 M . 0.250L = 1L . Diluted M
0.5M = Diluted M
The smaller number is the number of protons, and the greater number is the mass.