How many milliliters of an aqueous solution of 0.164 M chromium(II) bromide is needed to obtain 2.26 grams of the salt? ___

A 700.0 mL gas sample at STP is compressed to a volume of 200.0 mL, and the temperature is increased to 30.0°C. What is the new

dolphi86 [110]

Answer: The new pressure of the gas in Pa is 388462

Explanation:

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

$\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}$

where,

$P_1$ = initial pressure of gas at STP = $10^5Pa$

$P_2$ = final pressure of gas = ?

$V_1$ = initial volume of gas = 700.0 ml

$V_2$ = final volume of gas = 200.0 ml

$T_1$ = initial temperature of gas = 273 K

$T_2$ = final temperature of gas = $30^oC=273+30=303K$

Now put all the given values in the above equation, we get:

$\frac{10^5\times 700.0ml}{273K}=\frac{P_2\times 200.0ml}{303K}$

$P_2=388462Pa$

The new pressure of the gas in Pa is 388462

6 0

3 years ago

Define the boiling and evaporation using kinetic theory

expeople1 [14]

Answer:

Explanation:

By the kinetic molecular theory (particle model), all matter consists of particles, there are spaces between the particles, the particles are in constant random motion, and there are forces of attraction and repulsion between the particles.

Furthermore, temperature is defined to be a measure of the average kinetic energy of the particles.

Evaporation is a change of phase from liquid to gas explained as follows :

When particles in the liquid phase are heated, they gain kinetic energy and move faster and further apart. Eventually they have enough energy to escape the forces of attraction holding them together in the liquid phase and they move very fast and far from each other and exist in the gaseous phase.

5 0

2 years ago

Explain, in terms of element classification, why KBr is an ionic compound

enot [183]

LBr is ionic compound because k for potassium is metal which means it’s on the left side of the periodic table and Br which is bromine is a non metal which means is on the right side of the periodic table.

In Conclusion when a non metal and metal come together the are called ionic compound

5 0

3 years ago

For Na2HPO4:(( (Note that for H3PO4, ka1= 6.9x10-3, ka2 = 6.4x10-8, ka3 = 4.8x10-13 ) a) The active anion is H2PO4- b) The activ

Komok [63]

Answer:

Check the explanation

Explanation:

Answer – Given, $H_3PO_4$ acid and there are three Ka values

$K_{a1}=6.9x10^8, K_{a2} = 6.2X10^8, and K_{a3}=4.8X10^{13}$

The transformation of $H_2PO_4- (aq) to HPO_4^2-(aq)$ is the second dissociation, so we need to use the Ka2 = 6.2x10-8 in the Henderson-Hasselbalch equation.

Mass of KH2PO4 = 22.0 g , mass of Na2HPO4 = 32.0 g , volume = 1.00 L

First we need to calculate moles of each

Moles of KH2PO4 = 22.0 g / 136.08 g.mol-1

= 0.162 moles

Moles of Na2HPO4 = 32.0 g /141.96 g.mol-1

= 0.225 moles

[H2PO4-] = 0.162 moles / 1.00 L = 0.162 M

[HPO42-] = 0.225 moles / 1.00 L = 0.225 M

Now we need to calculate the pKa2

pKa2 = -log Ka

= -log 6.2x10-8

= 7.21

We know Henderson-Hasselbalch equation

pH = pKa + log [conjugate base] / [acid]

pH = 7.21 + log 0.225 / 0.162

= 7.35

The pH of a buffer solution obtained by dissolving 22.0 g of KH2PO4 and 32.0 g of Na2HPO4 in water and then diluting to 1.00 L is 7.35

6 0

3 years ago

When the energy is removed what will happen to a gas?

creativ13 [48]

Answer:

Hey mate 
I hope it helps

Explanation:

<h3>Removing Energy: Removing energy will cause the particles in a liquid to begin locking into place. A. Boiling and Evaporation: Evaporation is the change of a substance from a liquid to a gas. Boiling is the change of a liquid to a vapor, or gas, throughout the liquid.</h3>

<h2>PLZ MARK ME AS BRAIN LIST </h2>

THANKS 

8 0

3 years ago

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How many milliliters of an aqueous solution of 0.164 M chromium(II) bromide is needed to obtain 2.26 grams of the salt? ____mL