Answer:
1. B, D,
2.A, F
Explanation:
1. According to the law of conservation of mass, In a course of chemical reaction, matter can neither be created nor destroyed but can be changed from one form to another. This means the amount of matter at the begining and ending of a reaction must be thesame.
2. Chemical reaction is not easily reversible. when gas is produced, provided the reaction system is an open system, the gas cannot be recovered and the reactants cannot be recovered from the products. likewise color change are attributed to chemical reaction
Answer:
D
Explanation:
Nitrogen is a naturally occurring element that is essential for growth and reproduction in both plants and animals. It is found in amino acids that make up proteins, in nucleic acids, that comprise the hereditary material and life's blueprint for all cells, and in many other organic and inorganic compounds.
<h3><u> Answer</u>;</h3>
= 4.0 L
<h3><u>Explanation;</u></h3>
Boyle's law states that the volume of a fixed mass of a gas is inversely proportional to pressure at a constant temperature.
Therefore; <em>Volume α 1/pressure</em>
<em>Mathematically; V α 1/P</em>
<em>V = kP, where k is a constant;</em>
<em>P1V1 = P2V2</em>
<em>V1 = 0.5 l, P1 =203 kPa, P2 = 25.4 kPa</em>
<em>V2 = (0.5 × 203 )/25.4 </em>
<em> = 3.996 </em>
<em> ≈ </em><em><u>4.0 L</u></em>
Answer:
Aluminium oxide has higher melting point than aluminium chloride because there nay be some impurities in the oxide which affects the intermolecular force of attraction
<span>Chlorofluorocarbons (CFCs) can damage the ozone layer.</span>