Question

in group 13 (boron family), what element is classified as a metalloid? 1 point boron aluminum gallium indium which family contains elements that exist as two gases, one liquid (br), and two solids? 1 point halogens noble gases oxygen family nitrogen family how many neutrons are in phosphorus? * 1 point

Explanation:

First Sub - Question: In Group 13 (Boron Family), what element is classified as a metalloid?

In Group 13 (Boron Family), the elements are Boron (B), Aluminum (Al), Gallium (Ga), Indium (In), etc. Boron is a metalloid, while Aluminum, Gallium, and Indium are metals.

The Halogens family (Group 17) has elements: Fluorine (F) and Chlorine (Cl) are gases, Bromine (Br) is a liquid, and Iodine (I) and Astatine (At) are solids. The other families do not match this property. Noble Gases are mostly gases, Oxygen Family and Nitrogen Family do not have one liquid and two solids in the same way as Halogens.

Step 1: Recall the formula for neutrons

The number of neutrons ($n$) in an atom is calculated by the formula $n = A - Z$, where $A$ is the mass number and $Z$ is the atomic number.

Step 2: Find atomic number and mass number of Phosphorus

Phosphorus has an atomic number ($Z$) of 15. The most common isotope of Phosphorus has a mass number ($A$) of 31.

Step 3: Calculate the number of neutrons

Using the formula $n=A - Z$, we substitute $A = 31$ and $Z = 15$. So, $n=31 - 15=16$.

Answer:

A. Boron

Second Sub - Question: Which family contains elements that exist as two gases, one liquid (Br), and two solids?