Which methods could be used to dilute a solution of sodium chloride (NaCl)?

Differentiating Types of Gymnosperms

yan [13]

Answer:

the following in order:

1) conifer

2) gnetophyte

3) ginkgo

4) cycad

Explanation:

8 0

3 years ago

The following thermochemical equation is for the reaction of nitrogen(g) with oxygen(g) to form nitrogen dioxide(g). N2(g) + 2O2

Rzqust [24]

Answer: The mass of nitrogen gas reacted to produce given amount of energy is 5.99 grams.

Explanation:

The given chemical reaction follows:

$N_2(g)+2O_2(g)\rightarrow 2NO_2(g);\Delta H=66.4kJ$

We know that:

Molar mass of nitrogen gas = 28 g/mol

We are given:

Enthalpy change of the reaction = 14.2 kJ

To calculate the mass of nitrogen gas reacted, we use unitary method:

When enthalpy change of the reaction is 66.4 kJ, the mass of nitrogen gas reacted is 28 grams.

So, when enthalpy change of the reaction is 14.2 kJ, the mass of nitrogen gas reacted will be = $\frac{28}{66.4}\times 14.2=5.99g$

Hence, the mass of nitrogen gas reacted to produce given amount of energy is 5.99 grams.

8 0

4 years ago

a 25.0-ml volume of a sodium hydroxide solution requires 19.6 ml of a 0.189 m hydrochloric acid for neutralization. a 10.0- ml v

Rashid [163]

Concentration of NaOH = 0.148 molar, M

Concentration of H3PO4 = 0.172 molar, M

Concentration x Volume will give the number of moles of solute in that volume. C*V = moles

Concentration has a unit of (moles/liter). When multiplied by the liters of solution used, the result is the number of moles.

Original HCl solution: (0.189 moles/L)*(0.0196 L)= 0.00370 moles of HCl

The neutralization of 25.0 ml of sodium hydroxide, NaOH, requires 0.00370 moles of HCl. The reaction is:

NaOH + HCl > NaCl and H2O

This balanced equation tells us that neutralization of NaOH with HCl requires the same number of moles of each. We just determined that the moles of HCl used was 0.00370 moles. Therefore, the 25.0 ml solution of NaOH had the same number of moles: 0.00370 moles NaOH.

The 0.00370 moles of NaOH was contained in 25.0 ml (0.025 liters). The concentration of NaOH is therefore:

(0.00370 moles of NaOH)/(0.025 L) = 0.148 moles/liter or Molar, M

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The phosphoric acid problem is handled the same way, but with an added twist. Phosphoric acid is H3PO4. We learn the 34.9 ml of the same NaOH solution (0.148M) is needed to neutralize the H3PO4. But now the acid has three hydrogens that will react. The balanced equation for this reaction is:

H3PO4 + 3NaOH = Na3PO4 + 3H2O

Now we need three times the moles of NaOH to neutralize 1 mole of H3PO4.

The moles of NaOH that were used is:

(0.148M)*(0.0349 liters) = 0.00517 moles of NaOH

Since the molar ratio of NaOH to H3PO4 is 3 for neutralization, the NaOH only neutralized (0.00517)*(1/3)moles of H3PO4 = 0.00172 moles of H3PO4.

The 0.00172 moles of H3PO4 was contained in 10.0 ml. The concentration is therefore:

(0.00172 moles H3PO4)/(0.010 liters H3PO4)

Concentration of H3PO4 = 0.172 molar, M

5 0

1 year ago

How much energy is needed to completely boil a 5.05g sample of water?

Keith_Richards [23]

Given what we know, we can confirm that the amount of heat energy that would be required in order to boil 5.05g of water is that of 11.4kJ of heat.

<h3>Why does it take this much energy to boil the water?</h3>

We arrive at this number by taking into account the energy needed to boil 1g of water to its vaporization point. This results in the use of 2260 J of heat energy. We then take this number and multiply it by the total grams of water being heated, in this case, 5.05g, which gives us our answer of 11.4 kJ of energy required.

Therefore, we can confirm that the amount of heat energy that would be required in order to boil 5.05g of water is that of 11.4kJ of heat.

To learn more about the behavior of water visit:

brainly.com/question/1416592?referrer=searchResults

8 0

2 years ago

A particular atom contains 29 electrons, 34 neutrons, and 29 protons. what is the identity of this element and what is its atomi

IgorLugansk [536]

Answer:

Identity = Copper

Atomic Number = 29

Explanation:

Given Data:

Number of Electrons = 29

Number of Neutrons = 34

Number of Protons = 29

Identity and atomic number of Element:

This element can be identified by using two sources, i) Atomic Number ii) Electronic Configuration.

Atomic Number is defined as the number of protons present in the nucleus of an element. As the given number of protons are 29, therefore, the atomic number of this element is also 29.

Secondly, if the element is in neutral state then its number of protons must be equal to the number of electrons present in it. So, in neutral state this element will contain 29 electrons. Therefore, the electronic configuration is as follow,

1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d⁹

Now using electronic configuration one can easily identify the position of this element in periodic table. As the valence shell is 4, so it belongs to period 4 and there are 9 electrons in d-subshell so it belongs to transition elemnts and transition element with 9 electrons in d shell is Copper. Also, the stable electronic configuration of copper is written as,

1s², 2s², 2p⁶, 3s², 3p⁶, 4s¹, 3d¹⁰

5 0

3 years ago