Answer:
bonds within the nucleus of reactants atoms are broken and rearranged to form new product atoms
Answer:
(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
(b) ₁₀Ne: 1s² 2s² 2p⁶
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(a) 3
(b) 6
(c) 7
Explanation:
We can state the ground-state electron configuration for each element following Aufbau's principle.
(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
(b) ₁₀Ne: 1s² 2s² 2p⁶
Second part
(a) Al belongs to Group 13 in the Periodic Table. It has 13-10=3 electrons in the valence shell.
(b) O belongs to Group 16 in the Periodic Table. It has 16-10=6 electrons in the valence shell.
(c) F belongs to Group 17 in the Periodic Table. It has 17-10=7 electrons in the valence shell.
The question is incomplete:
Complete question is
The most efficient way to determine whether a reaction is an exothermic chemical
reaction is to use —
A) an oxygen probe
B) a temperature probe
C) a pressure probe
D) a pH probe
...............................................................................................................
Answer:
Reaction is said to be exothermic in nature, if heat is evolved from the system. The resultant product formed is more stable. Since, during exothermic reaction, heat is given out be the system, temperature of system will increase. Hence, temperature is the probe to determine exothermic reaction.
Thus, correct answer is option B) a temperature probe
Answer: 1.2 M
Explanation:
Given that:
volume of NaCl = 392 mL
Convert volume in milliliters to liters
(since 1000 mL = 1L
392 mL = 392/10000 = 0.392 L)
Concentration of NaCl = ?
Amount of moles of NaCl = 0.47 moles
Recall that the concentration of a solution depends on the amount of solute dissolved in a particular volume of solvent.
I.e Concentration in mol/L =
Amount in moles / Volume in liters
= 0.47 moles / 0.392 L
= 1.199 mol/L (Round up to the nearest tenth as 1.2 M)
Note that molarity is the same as concentration in moles per litres.
Thus, the molarity of 392 mL of solution that contains 0.47 mol NaCl is 1.2 M
