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2 years ago

What is the amount of heat released when 25g of water cools 12.5 degrees C ?

1 answer:

4 0

Water can't cool at a single temperature. It must start at a higher temperature, and drop to a lower temperature in order to cool. Unless we know the other temperature, there is no way to calculate the amount of thermal energy released.

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For each pair of gases, select one that most likely has the highest rate of effusion. Use the periodic table if necessary

brilliants [131]

You will do the highest one i think

4 0

2 years ago

Read 2 more answers

Given equilibrium partial pressures of PNO2= 0.247 atm, PNO = 0.0022atm, and PO2 = 0.0011 atm calculate the equilibrium constant

maxonik [38]

Answer 1:
Equilibrium constant (K) mathematically expressed as the ratio of the concentration of products to concentration of reactant. In case of gaseous system, partial pressure is used, instead to concentration.

In present case, following reaction is involved:

2NO2 ↔ 2NO + O2

Here, K = $\frac{[PNO]^2[O2]}{[PNO2]^2}$

Given: At equilibrium, PNO2= 0.247 atm, PNO = 0.0022atm, and PO2 = 0.0011 atm

Hence, K = $\frac{[0.0022]^2[0.0011]}{[0.247]^2}$
= 8.727 X 10^-8

Thus, equilibrium constant of reaction = 8.727 X 10^-8
.......................................................................................................................

Answer 2:
Given: PNO2= 0.192 atm, PNO = 0.021 atm, and PO2 = 0.037 atm.

Therefore, Reaction quotient = $\frac{[PNO]^2[O2]}{[PNO2]^2}$
= $\frac{[0.021]^2[0.037]}{[0.192]^2}$
= 4.426 X 10^-4.

Here, Reaction quotient > Equilibrium constant.

Hence, the reaction need to go to reverse direction to reattain equilibrium

5 0

2 years ago

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In the heat equation, what does Q represent? heat required to raise the temperature specific heat of the substance mass of the s

MaRussiya [10]

Answer: heat required to raise the temperature

Explanation: Heat equation is represented as:

$Q= m\times c\times \Delta T$

Q= heat required to raise the temperature

m= mass of the substance

c = heat capacity of substance

$\Delta T={\text{Change in temperature}}$

7 0

2 years ago

Read 2 more answers

What is the relationship between the sequence of DNA’s subcomponents and the properties of DNA? 1. The amino acid sequence along

wel

Answer:

Explanation:

There are four nitrogenous bases in a DNA including guanine (G), adenine (A), cytosine (C) and Thymine (T) and together they form the nitrogenous base sequence arranged in a specific order of three letters such as GAC and TAG to form a genetic code.

These nitrogenous base sequences forming genetic code are amino acid specific and determine the amino acid sequence in DNA. for example: CTT determines leucine and GTT determines valine.

Hence, the correct option is "3".

7 0

2 years ago

In each row, check the box under the compound that can reasonably be expected to be more acidic in aqueous solution, e.g. have t

vredina [299]

Answer:

$HCH_{3}SO_{2}$

$H_{3}PO_{3}$

$HClO_{2}$

Explanation:

Every acid (HA) tends to disolve into proton ( $H^{+}$ ) and anion ( $A^{-}$ ) in aqueous solution. Acid strength can be determined by measuring this tendency to separate into proton an anion. Strength of an acid can be quantified by its acid dissociation value - Ka. A strong acid will have a tendency to easily release proton and will have larger Ka value and smaller logarithmic value (pKa = - logKa) similar to calculating pH of the solution. So the easiest way to resolve this issue is by looking for Ka or pKa value of the acid (This table may be useful in more complex tasks and is attached below). However, stronger acid can be determined elsehow.

a) Carbon is element 14 with 4 valent electrons and sulfur is element 16 with 6 valence electrons. Thus, sulfur has stronger electronegativity (tendency to attract bonded electrons towards itself). This means that sulfur will hold oxygen tighter to itself so the hydrogen bond to it can be more easily separated from it. $HCH_{3}SO_{2}$ is more acidic in aqueous solution.

b) In $H_{3}PO_{4}$ , phosphorus holds one double bond with oxygen and three OH group equally. To show an acidic tendency, phosphorus would need to let go one hydrogen out of one of OH groups. In $H_{3}PO_{3}$ , phosporus holds two double bong with oxygen, one OH and one hydrogen, all single and lonely, ready to leave phosphorus and show acidic characteristics in aqueous solution. Thus, $H_{3}PO_{3}$ is more acidic compound.

C) In all Cl acids, the electron density is placed around Cl so the more oxygen around Cl, the more acidic will be the chemical. This is comparable to an oxidation state - the bigger oxidation state, the stronger acid will be:

$HClO_{4} ^{+7} >HClO_{3}^{+5} >HClO_{2}^{+3} >HClO_{}^{+1}$

$HClO_{2}$ can reasonably be expected to be more acidic in aqueous solution.

4 0

2 years ago