Answer:
Hello there! How are you doing today :] Sand would be a covalent bond.
Explanation:
Silica is one of the main compounds found in sand. It also contains many silicon and oxygen atoms. which; are joined together by covalent bonds in a regular arrangement, forming a giant covalent structure.
Amount of money that Cheryl has = $56
Cost of each notebook = $1.60
The maximum number of notebooks she can buy = n
Then
n = 56/1.6
is the inequality that shows the maximum number of notebooks she can buy with her money
On solving the inequality, we get
n = 35 notebooks.
Note that it says oxygen "gas"
So you need the atomic mass of oxygen gas
Look at your periodic table, you'll see 15.9994 under oxygen
Oxygen gas has a formula of O2 therefore,
(15.9994) times 2= Oxygen gas atomic mass=31.9988
Mol= Mass/Atomic Mass
=62.3 g/ 31.9988 g/mol = 1.95 mol
now look at the ratio of C2H6 and O2, notice there is an invisible number beside each of them, at that "invisible number" is =1
1 C2H6 + 1 O2 -> products
this means that for 1 mol of C2H6, 1 mol of O2 has to react with it
Thus as we have 1.95 moles of O2, we need 1.95 moles of C2H6
This assumption is not valid because, there are some elements which exist in two or more forms; they have the same atomic number but differ in their mass number, which meas that they possess different number of neutrons. These type of element are called isotopes. Isotope have the same atomic number and similar physical and chemical properties but they have different number of neutrons and therefore possess different masses.