Afusion reaction takes place between carbon and another element. neutrons are released, and a different element is formed. the different element is
a) lighter than helium. b)heavier than helium. c)the same weight as helium. d)dependent on the element that reacted with carbon.

Answer is: B) heavier than helium.

Helium (He) is an element with mass number 4 and carbon (C) is an element with mass number 12. Carbon has three time bigger mass numer, so new element is heavier thah helium.

For example, nuclear reaction: ²⁴⁹Cf + ¹²C → ²⁵⁷Rf + 4n°.

Californium-249 has mass number 259, carbon-12 has mass number 12 and rutherfordium-257 has mass number 257.

Mass number (A) is the total number of protons and neutrons in a nucleus.  

Sum of mass numbers of californium-249 and carbon-12 is 261 (249 + 12), but four neutrons are produced, so new element has mass number 257 (261 - 4).

B

Explanation:

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.