Assuming your average walking speed is 1.4 m/s, what time should you leave your house to arrive at school (0.84 km away) at 7:15?

The number of moles of a given mass of a substance can be found without knowing its molecular formula or molar mass. true false

Choose all the answers that apply. fluorine (f) has an atomic number of 9 and an atomic weight of 18.99. fluorine has a. 9 protons b. 10 neutrons c. 18 electrons d. an atomic mass of 19 e. at least one isotope

Apound is approximately 0.45 kilogram. a persons weighs 87 kilograms. what is the persons’s weight, in pounds, when expressed to the correct number of significant figures