The enthalpy of the reaction is 100 kJ and the reaction is endothermic in nature.
<u>Explanation:</u>
Enthalpy of any chemical reaction is the measure of the difference in the energy utilized for performing a reaction. As in the present case, it is stated that the initially, a chemical reaction has 356 kJ of energy and after ending the chemical reaction has 456 kJ of energy.
This means the energy is increased after the chemical reaction. So the heat energy is absorbed during the reaction. This kind of chemical reaction where the products are formed by absorbing energy from the surrounding is termed as endothermic reaction.
Enthalpy = Energy absorbed = 456-356 =100 kJ.
So, the enthalpy of the reaction is 100 kJ. And as the enthalpy is positive which means the energy is absorbed from the surroundings, so the reaction is endothermic in nature.
Answer:
pH =3.8
Explanation:
Lets call the monoprotic weak acid HA, the dissociation equilibria in water will be:
HA + H₂O ⇄ H₃O⁺ + A⁻ with Ka = [ H₃O⁺] x [A⁻]/ [HA]
The pH is the negative log of the H₃O⁺ concentration, we know the equilibrium constant, Ka and the original acid concentration. So we will need to find the [H₃O⁺] to solve this question.
In order to do that lets set up the ICE table helper which accounts for the species at equilibrium:
HA H₃O⁺ A⁻
Initial, M 0.40 0 0
Change , M -x +x +x
Equilibrium, M 0.40 - x x x
Lets express these concentrations in terms of the equilibrium constant:
Ka = x² / (0.40 - x )
Now the equilibrium constant is so small ( very little dissociation of HA ) that is safe to approximate 0.40 - x to 0.40,
7.3 x 10⁻⁶ = x² / 0.40 ⇒ x = √( 7.3 x 10⁻⁶ x 0.40 ) = 1.71 x 10⁻³
[H₃O⁺] = 1.71 x 10⁻³
Indeed 1.71 x 10⁻³ is small compared to 0.40 (0.4 %). To be a good approximation our value should be less or equal to 5 %.
pH = - log ( 1.71 x 10⁻³ ) = 3.8
Note: when the aprroximation is greater than 5 % we will need to solve the resulting quadratic equation.
Answer:
- CFJA17
- THZ561
- GJA561
- GH68
- N461
- DG56
- BSJ57
HOPE IT HELPS THANK ME LATER.
Answer:
Signs and symptoms of mental illness can vary, depending on the disorder, circumstances and other factors. Mental illness symptoms can affect emotions, thoughts and behaviors.
Examples of signs and symptoms include:
Feeling sad or down
Confused thinking or reduced ability to concentrate
Excessive fears or worries, or extreme feelings of guilt
Extreme mood changes of highs and lows
Withdrawal from friends and activities
Significant tiredness, low energy or problems sleeping
Detachment from reality (delusions), paranoia or hallucinations
Inability to cope with daily problems or stress
Trouble understanding and relating to situations and to people
Problems with alcohol or drug use
Major changes in eating habits
Answer:
The main function of the immune system is to provide immunity to the body. Immunity is the body's ability to protect itself from the pathogens it is exposed to. Immunity depends on the body's ability to differentiate between things that belong in the body and those that do not. The immune system's first line of defense includes physical and chemical barriers that are always ready and prepared to defend the body from infection.
The skin acts as a barrier against pathogens. Some structures of the first line of defense include the skin, mouth, eyes, ears, nose, and stomach. The skin produces sweat and oil that work together to keep pathogens from the entering the body. Saliva and tears contain substances the can destroy pathogens. The ears and the stomach help fight pathogens.The ears produce ear wax that prevent pathogens from entering the ears. The stomach produces a liquid the kills pathogens.
Mucus is produce by the nose, lungs, throat, and stomach. Mucus traps pathogens. Mucus also prevent pathogens from getting into deep tissues. Anyway, the very first line of defense against any invasion of the human body is a set of physical barriers between the inside of the body and the outer world.
*my notes from edge2020*
Hope this helps ^-^
