question 1
During a practical class in the laboratory, the Chemistry teacher asked his students to prepare four solutions, with a concentration of 0.5 mol/L, using distilled water and one of the salts below in each one from them:
I. sodium iodide (NaI);
II. silver bromide (AgBr);
III. lithium cyanide (LiCN);
IV. iron nitrate II [Fe (NO3)2].
At the end of this procedure, he asked them to measure the pH of each of the solutions. From this information, which of the solutions has a pH less than 7?
a) I and III.
b) I and IV.
c) II and III.
d) II and IV.
e) III and IV.
question 2
The neutralization reaction is defined as a chemical phenomenon in which an acid interacts with water, forming salt and H2O. In contrast, the salt hydrolysis reaction would be one in which the salt interacts with water and forms acid and base. Based on these concepts and the theory of salt hydrolysis, what will be the character of a solution prepared with a mixture of aluminum sulfate [Al2(ONLY34)3] and water?
a) acid.
b) basic.
c) neutral.
d) amphoteric.
e) na.
More questionsTextual cohesion is a necessary knowledge in textual production, since, without cohesion, the text tends to be inconsistent and impair the understanding of those who read it. In this series of videos, Professor Guga Valente explains the various types of cohesion with practical examples.
Watch our video class to learn about the main abolitionist laws in Brazil, that is, the legislation that promoted the emancipation of slaves gradually before the actualization of abolition itself, on May 13, 1888.
