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3 years ago

How does an elements period number related to the number of the energy level of its valence electrons?

1 answer:

3 0

<span>There is a direct correlation between the period number and the energy level for valence electrons. For example, the H and He elements, in period 1, have their outer electrons in the energy level "1". This continues down the rows: all the elements in period 2 have their principal energy level as n = 2, period 3 has n = 3, and so on.</span>

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Which particle has a negative charge?

sweet [91]

Answer: A

Explanation: Beta particles have a charge of -1

6 0

2 years ago

Read 2 more answers

(part 1 of 3) Copper reacts with silver nitrate through a single replacement. If 1.29 g of silver are produced from the reaction

ale4655 [162]

Answer:

See explanation.

Explanation:

Hello there!

In this case, according to the described chemical reaction, we first write the corresponding equation to obtain:

$Cu+2AgNO_3\rightarrow 2Ag+Cu(NO_3)_2$

Thus, we proceed as follows:

Part 1 of 3: here, since the molar mass of silver and copper (II) nitrate are 107.87 and 187.55 g/mol respectively, and the mole ratio of the former to the latter is 2:1, we can set up the following stoichiometric expression:

$m_{Cu(NO_3)_2}=1.29gAg*\frac{1molAg}{107.87gAg}*\frac{1molCu(NO_3)_2}{2molAg}*\frac{187.55gCu(NO_3)_2}{1molCu(NO_3)_2} \\\\m_{Cu(NO_3)_2}=1.12gCu(NO_3)_2$

Part 2 of 3: here, the molar mass of copper is 63.55 g/mol and the mole ratio of silver to copper is 2:1, the mass of the former that was used to start the reaction was:

$m_{Cu}=1.29gAg*\frac{1molAg}{107.87gAg}*\frac{1molCu}{2molAg}*\frac{63.55gCu)_2}{1molCu} \\\\m_{Cu}=0.380gCu$

Part 3 of 3: here, the molar mass of silver nitrate is 169.87 g/mol and their mole ratio 2:2, thus, the mass of initial silver nitrate is:

$m_{AgNO_3}=1.29gAg*\frac{1molAg}{107.87gAg}*\frac{2molAgNO_3}{2molAg}*\frac{169.87gAgNO_3}{1molAgNO_3} \\\\m_{AgNO_3}=2.03gAgNO_3$

Best regards!

5 0

2 years ago

What happens to raisins or other dried fruits in breakfast cereals when you pour milk over them? why?

viktelen [127]

<span>Dried fruits and raisins get terribly soggy after being drenched in milk for a long period of time. They act like a sponge, absorbing all of the milk up making them wet and "soggy". I prefer them to be like that when I eat my cereal in the morning.</span>

8 0

2 years ago

Which of the following is NOT a reason why index fossils are chosen for determining ages of rocks? Select all that apply.

Anarel [89]

Answer:

Lol

Explanation:

5 0

2 years ago

Part B Write the balanced chemical equation for the neutralization reaction that occurs when an aqueous solution of hydrobromic

Doss [256]

Answer:

HBr(aq) + LiOH(aq) → LiBr(aq) + H2O(l)

Explanation:

A neutralization reaction is a process in which an acid, aqeous HBr reacts completely with an appropriate amount of base, aqueous LiOH to produce salt, aqueous LiBr and water, liquid H2O only.

HBr(aq) + LiOH(aq) → LiBr(aq) + H2O(l)

Acid + base → Salt + Water.

During this reaction, the hydrogen ion, H+, from the HBr is neutralized by the hydroxide ion, OH-, from the LiOH to form the water molecule, H2O.

Thus, it is called a neutralization reaction.

4 0

2 years ago