Answer: Crocodiles and tigers both have four legs
Explanation: Even when sharks and tigers are both meat eaters, the question is about similarities between tigers and crocodiles, so D is out. A is about crocodiles and sharks, so it's out also. B suits for sharks too, so it's out too. C is the most suitable answer, because both animals have four legs, which means that they belong to the group of quadrupede animals.
Almost without exceptions, the alkali metals (Li, K, Na,...) are in oxidation state (I) and the alkaline earth metals (Be, Mg, Ca, ...) are in oxidation state (II).
So without confusion, the naming of the metal part is simply the metal name, such as calcium oxide.
The Stock system (which indicates the oxidation state) is required only when the metal exhibits multiple oxidation states, such as iron (II) oxide or iron (III) oxide.
Then again, older nomenclature applies the ending -ous to the lower oxidation state, and -ic to the higher. Using the Latin name ferrum for iron, the previous compounds were named ferrous oxide and ferric oxide respectively.
Answer:
C
Explanation:
The plate 'float' on top of the liquid magma. There are convection currents that circulate through the magma, and the techtonic plates are moved along with the magma.
Answer:
Nitrogen
Explanation:
The element nitrogen cannot be a product in the given reaction.
The reaction is;
HCl + CaCO₃
According to the law of conservation of matter, "matter is neither created nor destroyed in the cause of a chemical reaction".
The law suggests that, in a chemical reaction, we end up with the same species we started with. Although due to rearrangement of bonds, new compounds can form;
Starting atoms
H
Cl
Ca
O
These species will also be found in the product.
