A 25.0 mL sample of HCI reacted with 20.0 mL of 2.00 M NaOH. What is the molarity of the HCI? HCl(aq) + NaOH(aq) —> NaCl(aq) + H2O(l)
really need help!

Molarity of HCl = 1.6M

Explanation:

The chemical reaction equation is;

HCl(aq) + NaOH(aq) —> NaCl(aq) + H2O(l)

Now, molarity = number of moles/volume

Thus, for NaOH, we have;

Number of moles = molarity × volume = 2M × (20/1000) L

Number of moles = 0.04 moles

Using the coefficients in the chemical equation above, we can find the corresponding number of moles for HCl.

Number of moles of HCl = 0.04 moles NaOH × (1 mole of HCl/1 mole of HCl) = 0.04 moles of HCl

Thus;

Molarity of HCl = 0.04/(25/1000)

Molarity of HCl = 1.6M

explanation:

metals have excess of electrons whereas non-metals have deficiency of electrons. thus, in order to gain stability metals easily donate their electrons to the non-metals.

for example, electronic configuration of sodium is and electronic configuration of phosphorous is .

when a phosphorous atom and sodium atom combine together then sodium will donate is extra one electron to the phosphorous atom. as a result there will be formation of ionic bond between sodium and phosphorous.

the reaction will be as follows.

there, are three sodium sodium atoms and each of them will donate its one extra electron to phosphorous atom. thus, the sub-shell of phosphorous gets completely filled.  

thus, we can conclude that electrons are transferred from atoms of sodium to atoms of phosphorous. this transfer makes the sodium atoms donate one electron and the phosphorous atoms to gain one electron. as a result, the sodium and phosphorus atoms strongly attract each other.