What element is necessary for a healthy eye

The men's world record for running a mile outdoors (as of 1999) is 3 min 43.13 s. At this rate, how long would it take to run a 2 km race (1 mi = 1609 m) ?

Write about "human impact"

Choose the number of significant figures indicated 3.820

What contribution did john dalton make to chemistry?

Whats a particles wave

A scientist observes the boundary between two tectonic plates for a decade and finds that no new volcanoes have formed over the course of her investigation. Does this result support the theory of plate tectonics? Why or why not?

Why is it incorrect to balance a chemical equation by changing the subscripts?

A solution of CuSO4 is labelled 0.01 M. How much CuSO4 in grams, must be used to make 1 liter of solution? A) 1.120 g B) 1.595 g C) 1.6 g D) 15.0 g

Rank the following elements according to their ionization energy: tin krypton antimony arsenic

Water (3030 g) is heated until it just begins to boil. If the water absorbs 5.49*105 J of heat in the process, what was the initial temperature of the water?