An aqueous solution of 6.70 M ammonia, NH3, has a density of 0.950 g/mL. The percent by mass of NH3 in the solution is %.

12.01% by mass

Explanation:

Percent by mass is 100 times the mass of solute (ammonia) over the mass of the solution. In molarity, we have the moles of ammonia per liter of solution. There are 6.70moles of NH3 in 1L. Thus, we need to convert the moles of ammonia to grams and the liters of solution to grams:

Mass ammonia - Molar mass: 17.031g/mol-

6.70moles * (17.031g / mol) = 114.1g NH₃

Mass solution:

1L * (1000mL / 1L) = 1000mL * (0.950g/mL) = 950g

Percent by mass:

114.1g NH₃ / 950g * 100 =

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.

ugh fiel iente of insistí is did kiwis jaj