Answer:
A. a new substance is being produced.
Explanation:
The bubbles most likely indicates that a new substance is being produced by this reaction. In essence, we describe this sort of change as chemical change.
In a chemical change, new substances are usually produced. They are accompanied by the evolution or absorption of energy.
The reaction of Zinc with a strong acid to produce bubbles on the surface of the metal indicates a chemical change and the formation of a new kind of substance.
Take for example, let zinc reacts with hydrocholoric acid, HCl;
Zn + 2HCl → ZnCl₂ + H₂
Since Zn is higher than Hydrogen in the activity series, it will displace it from HCl and liberate hydrogen gas as a product. This will cause the bubbles observed in the reaction.
This is a chemical change and new products have been formed.
B and D are wrong because they are both physical changes.
C is wrong because no information about such is provided by the problem statement.
So, when a piece of zinc metal combines with a strong acid, a new kind of substance is produced.
Answer:
Because the gravitational force alters
Explanation:
Some patterns and trend that are present in the periodic table would be
1. electronegativity (from left-to-right it increases across the table)
2. ionization (from left-to right it increases and from bottom-to-top it increases)
3. electron affinity (same as ionization energy)
4. atom radius (increases opposite way; from right-to-left it increases and from top-to-bottom it increases)
5. melting point (higher melting points with metals and lower melting point with non-metals)
6. metallic character (same as atom radius)
<span>Phospholipids would have to form a phospholipid bilayer in order to achieve water on the outside and water inside. This is because the nonpolar tails of the phospholipids are facing each other in a water environment because they cannot interact with the water, only their own tails, while the phosphate heads of the molecule face the periphery of the tails and interact with water. Micelles are the simplest examples of these.</span>
