Sam burned propane to heat 500.0 g of water that had an
initial temperature of 20.0°C.
The heat added from the
burning of the propane was
84.6 kJ. What is the final
temperature of the water?

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

If equal masses of the listed metals were collected , which would have a greatest volume ? a. aluminum 2.70,b.zinc7.14,c.copper 8.92,d.lead 11.34

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture