Answer:
a. +2
b. +3
c. -1
Explanation:
The typical oxidation states can be determined from the periodic table based on the number of valence electrons an atom has.
a. Calcium belongs to group 2A, meaning it has 2 valence electrons and, therefore, would have an oxidation state of +2 in compounds.
b. Aluminum is in group 3A, meaning it has 3 valence electrons and would have an oxidation state of +3 in compounds when the 3 electrons are lost.
c. Fluorine would become fluorine if it gained 1 additional electron to achieve an octet, so its oxidation state would be -1.
Answer:
18.2 g.
Explanation:
You need to first figure out how many moles of nitrogen gas and hydrogen (gas) you have. To do this, use the molar masses of nitrogen gas and hydrogen (gas) on the periodic table. You get the following:
0.535 g. N2 and 1.984 g. H2
Then find out which reactant is the limiting one. In this case, it's N2. The amount of ammonia, then, that would be produced is 2 times the amount of moles of N2. This gives you 1.07 mol, approximately. Then multiply this by the molar mass of ammonia to find your answer of 18.2 g.
Three classes: 28×3=84 students
8 test tubes per student: 84× 8= 672
hope this helps!
Answer:
1. Ionic bonding
2. Covalent bonding
3. Metallic bonding
Explanation:
Ionic bonding also referred to as electrovalent bonding is a kind of chemical bonding that involves the transfer of electrons between the valence shells of two elements with a large electronegativity difference usually a metal and a nonmetal.
For example an ionic bonding scenario might play out between a group one metal and a group seven halogen. While group one metals have one electron hindering their stability, group seven halogens need that one electron that could make them achieve this stability. It is this that causes them to come together in a way where the electron is transferred completely from the valence shell of the group 1 atom and accepted into the valence shell of the group 7 halogen.
Covalent bonding involves the sharing of electrons between atoms of comparable electronegativities. The electro negativity difference is not large enough to permit the total movement of the electrons and hence the electrons are then controlled by the nuclei of the two atoms
Between two metals, what we have is called the metallic bonding
A variable is not consistent or having a fixed pattern; liable to change.
