What fraction of a Sr-90 sample remains unchanged after 87.3 years?

What is hydrogen bond?

At birth, a lion cub is: Weak and dependent on its mother Strong enough to live on its own Able to get it's own food An exact copy of its mother

The periodic law states that the physical and chemical properties tend to repeat periodically when elements are arranged according to what trend

Name 4 other gases in the atmosphere besides oxygen and nitrogen

Give the oxidation number of the element indicated for each compound. a) carbon in Na2C2O4 b) nitrogen in HNO3 c) sulfur in H2SO4 d) carbon in HCO3 - e) manganese in KMnO4 f) chromium in Cr2O7 2-

During what phase of the moon can a lunar eclipse occur? A) new moon B) first quarter C) waxing gibbous D) full moon

All bodies of water make up a earth's A. atmosphere B. asthenosphere C. hydrosphere D. lithosphere

Which characteristic provides clues to how igneous rocks were formes? A textures B color C luster D streaks

If your heart beats an average of 68 times per minute, how many times will your heart beat in an hour? In a day? In a week? Show all work

The gas described in parts a and b has a mass of 1.66 g. the sample is most likely which monatomic gas?