Consider the nuclear equation below.

which correctly identifies the type of reaction?

a) alpha decay
b) beta plus decay
c) beta minus decay
d) gamma decay

Answer is: B) beta plus decay.

Beta decay is radioactive decay in which a beta ray and a neutrino are emitted from an atomic nucleus.

There are two types of beta decay: beta minus and beta plus.  

In beta plus decay, a proton is converted to a neutron, positron and an electron neutrino, so mass number (A) does not change.

In this nuclear reaction, oxygen (atomic number 8) changes to nitrogen (atomic number 7), because oxygen lost one proton, mass number stays the same (A = 15).

the leaf is an organ of a typical plant, and the main functions are to complete photosynthesis and allow the plant to exchange gas, just like how we have the respiratory system. leaves have the stomata, which collects maintains co2 and o2 levels. this is necessary for cell metabolism. the leaf also collects sunlight using chloroplasts. succinctly, leaves own a pivotal role in sustaining plant life.

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