Answer:
B) it is endothermic and the temperature decreased
Explanation:
Chemical reactions can be classified as endothermic and exothermic.
Endothermic reactions proceed with the absorption of heat energy (q) and have a positive value for q.
In contrast, Exothermic reactions proceed with the liberation of heat energy (q) and have a negative value for q.
It is given that the value of q = +450 J. Since q is positive, this implies that heat energy is absorbed from the surroundings resulting in a fall in temperature. Hence the reaction is endothermic.
Answer:
Densities of the solids and the liquids are expressed in units of grams per cubic centimeter (g/cm³) or in grams per milliliter (g/mL).
Densities of the gases are usually expressed in the units of grams per liter (g/L).
Explanation:
Density of a substance can be defined as the ratio of its mass and its volume.
The constituting atoms in the solids and liquids are fairly packed closely together.
<u>In general, a 1 cm³ or 1 mL volume of most of the solids and the liquids has mass of several grams.</u> Thus, densities of the solids and the liquids are expressed in units of grams per cubic centimeter (g/cm³) or in grams per milliliter (g/mL).
The constituent atoms or the molecules in the gases are far apart from each other when compared to the solids and the liquids.
<u>Thus, gases are much less dense and even about 1 L of gas have mass in range close to 1 gram.</u> Thus, densities of the gases are usually expressed in the units of grams per liter (g/L).
<u>Also, the density of the gases also depend upon the pressure and the temperature but these factors much not influence the density of the solids and the gases.</u>
Methionine is an amino acid and like some amino acid, it has a zwitterion form. A zwitterion form is a form of molecule showing separate positive and negative charges. The hydrogen from the carboxylic acid group will transfer to the amino group producing a negative charge at the carboxyl group and a positive charge at the amino group.
