1. Element X has two naturally occurring isotopes. Its first isotope has a mass of 28.0 amu and a natural abundance of 64.24%. Its second isotope has a mass of 25.0 amu.
What is the atomic mass of element X?

A100-watt light bulb radiates energy at a rate of 100 j/s. (the watt, a unit of power or energy over time, is defined as 1 j/s.) if all of the light emitted has a wavelength of 525 nm , how many photons are emitted per second?

The kw for water at 0 °c is 0.12× 10–14 m2. calculate the ph of a neutral aqueous solution at 0 °c.

Which statement explains which thermometer is more appropriate to measure the temperature of a liquid at 43.6 degrees celsius a) thermometer a, because it measures temperature more accurately than thermometer b b) thermometer b, because it measures temperature more accurately than thermometer a c) thermometer a, because it measures temperature more precisely than thermometer b d) thermometer b, because it measures temperature more precisely than thermometer a