Answer: 4.22 grams of solute is there in 278 ml of 0.038 M 
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
where,
n = moles of solute
= volume of solution in L
Now put all the given values in the formula of molality, we get

mass of
= 
Thus 4.22 grams of solute is there in 278 ml of 0.038 M 
Explanation:
We know that,
1 mile = 1609.34 m
We need to find how many meters are present in the 12.45 miles. To find it use unitary method as follows :
12.45 mile = 1609.34 × 12.45
12.45 mile=20036.283 meters
or

Hence, this is the required solution.
<h2>
NH3 is a weak alkali that does not dissociate fully into its solution. Which of the following is true about NH3?
</h2><h2>
</h2><h2>
A. It has a very low pH.
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B. It's dissociation is a reversible reaction.
</h2><h2>
C. It has a high H+ concentration.
</h2><h2>
D. It will release all of its OH- ions.</h2>
Explanation:
<h3>
NH3 is a weak alkali that does not dissociate fully into its solution: It's dissociation is a reversible reaction.
</h3><h3>
</h3>
Reactions are also :
Reversible reaction
A reaction in which products can combine back to give reactants under same given condition .
Example : N₂+H₂-------NH₃
Irreversible reaction
A reaction in which the products cant combine back to give reactants under same set of conditions .
Example : Burning of paper
According to the law of conservation of mass, the amount of BARIUM present of the reactants is the same as the amount present in the products (the precipitate).
(11.21 g BaSO4) / (233.4 g/mol BaSO4) = 0.0480 mol BaSO4 and original barium salt
(10.0 g) / (0.0480 mol) = 208.3 g/mol
So it must have been BaCl2, because the molar mass of Barium is 137 which leave 71 grams left. Since Barium is a +2 charge, it means the atom next to it must be twice. Chlorine mass is 35, which twice is 71
When you are tuning an instrument it changes the sound of the instrument