In the measurement 0.502 L, which digit is the estimated digit? A. 5 B. 3 C. The 0 to the left of the decimal point D. The 0 immediately to the left of the 3

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

Answer

it is the minimum amount of material needed to sustain a fission reaction.

explanation

critical mass is the minimum amount of fissionable material that must be assembled for a sustained fission reaction to take place. although two to three neutrons are produced for every fission, not all of these neutrons are available for continuing the fission reaction. if the conditions are such that the neutrons are lost at a faster rate than they are formed by fission, the chain reaction will not be self-sustaining.   at the point where the chain reaction can become self-sustaining, this is referred to as critical mass.

Alfred wegener was a scientist who proposed the continental drift theory in the early twentieth century .simply put , his hypothesis propose that the continents had once been joined and overtime have drifted a part .

N= 3.2 moles, t = 50 + 273 = 323 k, p = 101.325 kpa, r = 8.314 l.kpa/k.mol pv = nrtv = nrt / p substituting.v = (3.2 mole)(8.314 l.kpa/k.mol )(323 k) / (101.325 kpa)hope this