Answer:
Similarities:
- Both are based on observation.
- Both are supported by empirical data
- Both are tested repeatedly
- Both are accepted by science
- Both are based on natural phenomena
Differences:
- Scientific law just describes a phenomenon. It does not give an explanation as to why the phenomenon occurs. It predicts an outcome of an event based on its initial condition.
- Scientific theory gives an explanation as to why an event had occurred.
- Laws are more resistant to change.
- Theories can be refuted and accepted, and develop other theories as well
Take note:
A scientific theory cannot be "upgraded" into a law, and a scientific law cannot be changed into a theory.
Answer:
A & D
Explanation:
A single-displacement reaction is a chemical reaction whereby one element is substituted for another one in a compound and thereby generating a new element and also a new compound as products.
From the options, only options A & D fits this definition of single-displacement reactions.
For option D: Both left and hand and right hand sides each have one element and one compound. We can see that K is substituted from KBr to join Cl to form KCl and Br2 on the right hand side.
For option A: Both left and hand and right hand sides each have one element and one compound. We can see that OH is substituted from 2H2O to join Mg to form Mg(OH)2 and H2 on the right hand side.
The other options are not correct because they don't involve only and element and a compound on each side of the reaction.
Answer:
(a) The resistance of 25m of wire is 3 ohms
(b) the length of this wire that has resistance 22 ohms is 183.33 m
Explanation:
Given;
resistivity of the wire, ρ = 0.12 ohms per meter
(a) The resistance of 25m of wire is calculated as follows;
(b) the length of this wire that has resistance 22 ohms is calculated as;
2 is sedimentary and 3 is metamorphic
