Answer:
a. energy changes during heating.
b. energy changes during chemical reactions.
c. color changes during chemical reactions.
d. Both (a) and (b)
Explanation:
The answer is D.Both (a) and (b)
Answer:
E) less than 7
Explanation:
pH is defined as the negative logarithm of the concentration of hydrogen ions.
Thus,
pH = - log [H⁺]
pH scale generally runs from 1 to 14 where pH = 7 represents neutral medium, pH < 7 represents acidic medium and pH > 7 represents basic medium.
Strong acids dissociate completely and when they react with base they form a salt of weak base and strong acid.
For example,
is a weak base and
is the hydrochloric acid.
So,

<u>Thus, the salt is of weak base and strong acid which corresponds to pH less than 7.</u>
The combustion of hexane (C6H14), a component of gasoline, is represented by the balanced chemical equation: 2 C6H14(l) + 19 O2(g) " 12 CO2(g) + 14 H2O(g). If 1.0 mole of hexane undergoescombustion, moles of O2 are required.
Optimization helps you make better choices when you have all the data, and simulation helps you understand the possible outcomes when you don’t. Frontline Solvers enable you to combine these analytic methods, so you can make better choices for decisions you do control, taking into account the range of potential outcomes for factors you don’t control.
Answer:
See explanation
Explanation:
Q1:
Chlorine has 17 protons while magnesium has only 12 protons. Recall that the Zeff depends on the size of the nuclear charge. The greater the size of the nuclear charge, the larger the Zeff experienced by a valence electron.
Q2:
The larger the Zeff, the smaller the atomic radius. Since the valence electrons of Cl experience a greater Zeff than those of Mg due to greater size of the nuclear charge, the atomic radius of chlorine will be smaller than that of Mg.
Q3:
The radius of an atom increases as the value of the principal quantum number (n) increases down the group due to addition of more shells. The greater the number of shells added, the greater the principal quantum number (n) and the greater the atomic radius, hence the answer.