Answer:
B. A chemical change occurred which caused the liquid's physical properties to change.
Explanation:
The reduction of the temperature of the system meant that the reaction absorbed heat energy from it. This shows that a chemical reaction was in progress. New products were formed, and this is proved by the change in the color to blue.
Answer: B. The element called tin is a metal with the chemical symbol Sn.
Explanation:
A is incorrect because Ni is Nickel, not Niobium.
C is incorrect because Carbon is a nonmetal and its symbol is C, not Cr.
D is incorrect because Copper's symbol is Cu, not Ce.
E is incorrect because As is the symbol for Arsenic, not Astatine.
1: True
2: True
3: False
4: False
(Question 2 might not be true, not sure)
Answer:
It depends on where it's located on the periodic table.
Explanation:
Metals are on left side of the periodic table except Hydrogen (H), which is a nonmetal, then there's the staircase, which has the metalloids, and on the right of the staircase are the nonmetals.