Question

1. Boron (B), Silicon (Si), Geranium (Ge), and Arsenic (As) are elements that have properties that fall between those of metals and non-metals. What common label could you apply to these elements? (1 mark) 2. Among the alkaline earth metals in Group 2A, which is more reactive - beryllium (element 4) or strontium (element 38) (1 mark) 3. Why do the element in a group have similar properties? (1 mark) What are three properties of metals? (2 marks)

hi can you help with those questions, please

Answer 1

I can!

1. Due to their properties being somewhere in between those of metals and those of non-metals, these elements are called "metalloids".

2. Metals in the 2A group usually react by loosing their outer-shell electrons. So the easier they can loose these electrons, the more reactive they are. How easy the outer shell electrons are lost is related to how strongly they are attracted to the nucleus of the atom. As you go down in a group, there are more electron shells between the outer shell and the atom, that shield the effect of the nucleus on these outer electrons. This means that they "feel" less attracted to the nucleus and are more prone to be lost. Consequently, as one goes down in a group the reactivity increases, which means that strontium is more reactive than beryllium.

3. Elements in a group have similar chemical properties because they have the same number of electrons in their outermost shell (known as valence electrons). Since chemical properties are usually related to reactions, and reactions are dependent on these "frontier" electrons, sharing the same number of valence electrons means sharing chemical properties.

4. They are good conductors of electricity, they are good conductors of heat and they present a typical "metal shine", given by their capacity to reflect light in a very effective manner.