The answer is A or B, I would put B.
Answer: ₉₈²⁵³Cf
253 is a superscript to the left of the symbol, Cf, which represents the mass number, and 98 is a subscript to the left of the same symbol, which represents the atomic number.
Explanation:
1) The alpha decay equation shows that the isotope Fm - 257, whose nucleus has 100 protons and 157 neutrons, emitted an alpha particle (a nucleus with 2 protons and 2 neutrons).
2) Therefore:
i) the mass number decreased in 4, from 257 to 257 - 4 = 253.
2) the atomic number decreased in 2, from 100 to 100 - 2 = 98.
3) Hence the formed atom has atomic number 98, which is californium, Cf, and the isotope is californium - 253.
4) The item that completes the given alpha decay reaction is:
₉₈²⁵³ Cf.
5) The complete alfpha decay reaction is:
₁₀₀²⁵⁷ Fm → ₉₈²⁵³Cf + ₂⁴He
You can verify the mass balance:
257 = 253 + 4, and
100 = 98 + 2
Zero is the value of water potential of pure water at atmospheric pressure.
<h3>
<u>Answer:</u></h3>
<u>1 mole of a gas at STP occupies 22.4 L volume </u>
<u>Now the volume is given =78.4 therefore,</u>
<u>No. of moles of gas = 78.4 ÷ 22.4 = 3.5 moles</u>
<u>I hope it helps you~</u>
Answer:
By heating the solution
Explanation:
Physical changes and chemical changes are the two types of changes that a substance undergoes. Physical change does not alter the substance's chemical composition, hence, can be easily reversed. There is also no new product formed. This is contrary to the occurrences of a chemical change, which cannot be reversed after a new product has been formed.
A physical change is what occurs when Adrian's teacher dissolves some sugar in a beaker of water to form a sugar solution. This change does not involve any new product formation, hence, can be reversed. The sugar can be derived back from the solution by HEATING THE SOLUTION. The water (solvent) will evaporate and the sugar (solute) will precipitate.