How many molecules are in 4.2 miles of water?

Which of the following is not a response? only one Aa tree turning its leaves towards the sun Ba mushroom appearing wet in the rain Ca protozoa contracting when touched Dyour stomach rumbling when you smell food

Which of the following can only be separated into two or more pure substances by a chemical change? a. an element b. a compound c. a homogeneous mixture d. a heterogeneous mixture

You place a glass of water in the freezer. Hours later the glass of water has frozen solid. What happened to the particles in the glass? A. They started to move freely. B. They slowed down and packed together. C.

For the chemical reaction CH3Br + OH - → CH3OH + Br-, which of the following would indicate the reaction occurred? a. decrease in CH3OH concentration over time b. increase in OH - over time c. increase in CH3Br over time d.

Solutions of hydrogen in palladium may be formed by exposing pd metal to h2 gas. the concentration of hydrogen in the palladium depends on the pressure of h2 gas applied, but in a more complex fashion than can be described by henry's law.

Which represents the balanced nuclear equation for the beta plus decay of C-11? Superscript 11 subscript 6 upper C right arrow superscript 11 subscript 5 upper B plus superscript 0 subscript plus 1 e.

Make a prediction for how to identify an unknown element and the chemical composition of a star

The density of HCN (hydrogen cyanide) gas at STP is 1.21g/L. What volume will 100.0g of HCN occupy at STP? A) 121 L B) 0.012 L C) 82.6 L D) none of the above

A 20.0 ml sample of 0.150 m ethylamine is titrated with 0.0981 m hcl. what is the ph after the addition of 5.0 ml of hcl? for ethylamine, pkb = 3.25

Some polymers are elastic because they are made of a. carbon. c. sugar and alcohol. b. phosphate ladders. d. cross-linked chains.