Which of these substances are elements?

quartz

water

iodine

lead

silicon

silicone

Which of the following will allow more solute to be dissolved in a solvent? Choose all that apply. * Adding more solute Cooling the solution Agitating the solution Adding heat Using larger crystals

What is formed from a metal and a non-metal

Who proposed that the atom had a positivley charged nucleus as its center

Why can scientists get energy from plants

Name two drying agents that can be use to dry hydrogen gas

What happens to an isotopes during radioactive

Why does the effective nuclear charge increase across a row of the periodic table?

Iodine-131 decays to form xenon-131. the half-life of this reaction is 8.07 days. from a 200-g sample of iodine-131, how much of the sample is xenon-131 after 16.14 days?

Complete the following statement by checking all that apply Creativity allows scientists to develop multiple approaches to solving problems. adapt to changes in scientific knowledge. look at old problems in new ways.

The atomic weight of hydrogen is 1.00794. a. True b. False