Does a solution have to involve a liquid? Explain your answer

Isotopes of elements have different:

A substance in the solid phase (state) of matter has A. a definite shape and a definite volume B. a definite shape, but no definite volume C. No definite shape, but a definite volume D. no definite shape and no definite volume

What is the force that opposes the sliding motion of two touching surfaces?

Based on the standard free energies of formation, which of the following reactions represent a feasible way to synthesize the product? A. 2C (s) + H2 (g) ? C2H2 (g); ? G? f=209.2 kJ/mol B. C (s) + O2 (g) ? CO2 (g); ? G? f=?394.4 kJ/mol C.

cells that perform a specific function in an organism A. are all the same B. can survive on their own C. are specialized D. perform all of the functions

After 10 years, 75 g of an original sample of 100 g of a certain radioactive isotope has decayed. the half-life of the isotope is

When 10.7 g of Al are reacted with 42.5 g of HCl, what volume of H2 will be produced at 47 C and 725 mmHg? Formula: 2Al+6HCl=2AlCl3+3H2

Increasing the temperature increases the rate of a many reactions by:

2A balloon filled with helium occupies 20.0 L at 1.50 atm and 25°C. How many moles of helium will there be in the balloon at STP? A. 22.4 moles B. 1.12 moles C. 0.0446 moles D. 0.893 moles E. 1.23 moles F. 4.55 moles

1. Which has a larger radius Ca atom or Ca+2 ion? 2. Which has a greater radius F atom or F - ion? 3. Which is the correct way of understanding the trend for Ionic radius Vs. Atomic radius?