Which action demonstrates a chemical change? A. ice melting into water B. wood becoming charred and black from burning C. water evaporating from a sugar solution, leaving behind sugar crystals D. a balloon suddenly popping

How many valence electrons do the alkali metals possess?

Mrs. Allen is about to have another baby. She already has three daughters. What is the probability that her fourth child will also be a girl?

Total energy of a system including potential and kinetic

How can we recognize polar and no polar molecules?

Which physical method can be used for obtaining a sample of salt from a small beaker of salt water? boiling freezing filtration sorting

what is the volume of 0.98 mol oxygen (O2) gas at 275 K and a pressure of 2.0 atm? (the universal gas constant is 0.0821 L*atm/mol*K)

Which element is classified as an alkali metal? Rb Sr Zr Cl

Which statements about a neutral atom are correct? Check all that apply. The positively charged particles in the nucleus are positrons. The radius of the electron cloud is twice as large as the radius of the nucleus.

The STP conditions are ... a) 0C and 1 atm b) 0C and 760 kPa C) 0K and 1 atm d) 0K and 760 kPa

Which of these radioactive waste elements would be stored at New Mexico's Waste Isolation Pilot Plant? A) Carbon: C (atomic number 6) B) Lead: Pb (atomic number 82) C) Uranium: U (atomic number 92) D) Plutonium: Pu (atomic number 94)