Can't really plot a graph here for question 1.
2a) The car speeds up from A to B. The car travels at a constant speed from B to C. The car slows down to a stop from C to D.
b) From the graph, at 10 seconds, the car is moving at 20 m/s.
Answer:
C. CT
Explanation:
It stands for Computed Tomography Scans.
Answer:
B. 1200
Explanation:
60 sec in one min in 2 min there will be 120 sec. 10x120=1200
Alkali metals: left column of your periodic table (not hydrogen, but anything below it). They have one valence electron, which they are happy to share in a reaction.
Halogens: second column from the right of your periodic table. They are one electron short of a full shell, so they are reactive in the opposite way that alkalis are--they want electrons.
Atomic number (number of protons) is the big number on the periodic table square. Hydrogen's is 1.
Atomic mass is a little number down below. For example, Hydrogen's is 1.008.
Neutrons are a tricky subject, because different isotopes of the same element can have different numbers of neutrons. You can't generally get this from the atomic mass, because the atomic mass is a weighted average of naturally occurring isotopes. Hydrogen can have 0,1, or 2 neutrons. To answer this, you'd have to choose a particular isotope from the table of isotopes (a completely different chart from the periodic table) which has a certain number of neutrons: n = weight - Z.
Valence electrons are the electrons in the outermost shell. (The column of the table).
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Number of principal shells is the row of the periodic table. </span>
I believe it’s B; Theories may be proven to be true and become laws.
A would make sense if we were talking about hypotheses however, we’re not.
