The hot, expanding gases generated by the combustion reaction in the engines are:
O A. released through the back of the engine to propel it and the
airplane forward.
B. used to move the pistons, which help to propel the airplane.
O c. used to provide lift for the airplane.
O D. used to move the wings.

What record? the question is incomplete

Answer the molar mass of magnesium is 24.305g/mol.

Answer:             1.0  × 10⁻⁵ msolution:                     as we know ph is given as,                                    ph  = -log [h⁺]and,                                    [h⁺]  =  10^-ph    (1)putting value of ph in eq. 1,                                    [h⁺]  =  10⁻⁵                                    [h⁺]  =  1.0  × 10⁻⁵ m