Uma estação de rádio opera com frequência de 600 kHz. Sendo a velocidade da onda eletromagnética no ar igual a 3.10^8 m/s, qual é o comprimento dessa onda de rádio?

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

Scientists are often interested in knowing the molar heat of combustion – the heat released during the combustion of one mole of a substance. use the periodic table to find molar masses. how many moles of ethanol are present in the sample?

Which is true according to the law of conservation of energy