what is the molarity of the following substances:

a. 35.0g naoh in 100ml h2o

b. 20.0g cucl2 in 350ml h2o

c. 3.35g caco3 in 500ml h2o

in advance : )

a. 8.75 M NaOH

b. 0.425 M CuCl₂ or 0.43 M CuCl₂

c. 0.067 M CaCO₃ or 0.07 M CaCO₃

Step-by-step explanation:

Molality is computed using the formula:

So first thing you need to do is determine how many moles of solute there are and divide it by the solution in liters.

Converting mass to moles, you need to get the mass of each solute per mole. You can use the periodic table to get the atomic mass (which is the grams per mole of each atom) of each of the elements involved. Then add them up and you will have how many grams per mole of each compound.

1. 35.0g of NaOH in 100ml H₂O

Element         number of atoms            atomic mass           TOTAL

Na                              1                   x             22.99g/mol  =    22.99g/mol

O                                1                   x             16.00g/mol   =    16.00g/mol

H                                1                   x                1.01g/mol   =       1.01g/mol

                                                                                                 40.00g/mol

This means that the molecular mass of NaOH is 40.00 g/mol

Then we use this to convert 35.0g of NaOH to moles:

Now that you have the number of moles we divide it by the solution in liters. Before we can do that you have to conver 100ml to L.

Then we divide it:

2. 20.0g CuCl₂ in 350ml H₂O

Element         number of atoms            atomic mass           TOTAL

Cu                              1                   x             63.55g/mol  =    63.55g/mol

Cl                               2                   x             34.45g/mol   =   70.90g/mol

                                                                                                134.45g/mol

350ml = 0.350L

3. 3.35g CaCO₃ in 500ml

Element         number of atoms            atomic mass           TOTAL

Ca                              1                   x             40.08g/mol  =    40.08g/mol

C                                1                   x              12.01g/mol   =    12.01g/mol

O                                3                  x              16.00g/mol   =   48.00g/mol

                                                                                                100.09g/mol

500ml = 0.5L

answer: the answer is 127 degrees

answer

a,b, and d

explanation

a reflection angle is more than

but less than;

an angle that measures

is a reflex angle.(true)

an angle that measures less than

is acute.(true)

provided we are considering angles greater or equal to zero.

an acute angle lies in the range.

an obtuse angle is less than 180° but more than 90°

an angle that measures 300° is obtuse (false)

an angle that measures 65° is an acute angle.(true)