1.Hans and Zacharias Janssen created the first microscope.
2.Robert Hooke was the first to use the word “cell.”
3.Anton van Leeuwenhoek observed small organisms he called “animalcules.”
4.Matthias Schleiden theorized that plants are made of cells.
5.Theodor Schwann theorized that animals are made of cells.
6.Rudolf Virchow theorized that cells come from other pre-existing cells.
Guess and check, test, trial and error, completion.
The answers are the following that can be answered using the chart:
A. Which type of hurricane is expected to strike more frequently this century?
Category 4 + 5C. In general, will hurricanes likely become stronger or weaker this century?
Stronger, because there are more stronger ones thant he weaker ones that can result to hurricane.
E. Which types of hurricanes are expected to drop in frequency by more than 25% this century?
Categories 1, 2, 3
Answer:
Fe is the anode and Sn is the cathode; NO3- ions flow into half-cell compartment (A) and Na ions flow into half-cell compartment (B).
Explanation:
The purpose of a salt bridge in a voltaic cell is not to move electrons from the electrolyte, it's main function is the maintenance of charge balance between the half cells .The electrons flow from the anode to the cathode.
The iron half cell which has a higher reduction potential serves as anode. Iron atoms give up electrons to form positive ions according to the equation;
Fe(s)-----> Fe^2+(aq) + 2e
Hence there will be an excess of positive ions in the anode (compartment A). NO3^- ions from the salt bridge will migrate towards this compartment to ensure charge balance.
Similarly, in compartment B(cathode) Sn^2+ ions will accept two electrons according to the reaction;
Sn^2+(aq) + 2e ------> Sn(s)
This reaction causes a depletion of positive ions in compartment B, hence Na^+ from the salt bridge move towards this compartment to ensure charge balance.
