Answer:
1. d. The reaction is spontaneous in the reverse direction at all temperatures.
2. c. The reaction is spontaneous at low temperatures.
Explanation:
The spontaneity of a reaction is associated with the Gibbs free energy (ΔG). When ΔG < 0, the reaction is spontaneous. When ΔG > 0, the reaction is non-spontaneous. ΔG is related to the enthalpy (ΔH) and the entropy (ΔS) through the following expression:
ΔG = ΔH - T. ΔS [1]
where,
T is the absolute temperature (T is always positive)
<em>1. What can be said about an Endothermic reaction with a negative entropy change?</em>
If the reaction is endothermic, ΔH > 0. Let's consider ΔS < 0. According to eq. [1], ΔG is always positive. The reaction is not spontaneous in the forward direction at any temperature. This means that the reaction is spontaneous in the reverse direction at all temperatures.
<em>2. What can be said about an Exothermic reaction with a negative entropy change?</em>
If the reaction is exothermic, ΔH < 0. Let's consider ΔS < 0. According to eq. [1], ΔG will be negative when |ΔH| > |T.ΔS|, that is, at low temperatures.
Answer:
A star begins its life as a cloud of dust and gas (mainly hydrogen) known as a nebula. A protostar is formed when gravity causes the dust and gas of a nebula to clump together in a process called accretion. ... If a critical temperature in the core of a protostar is reached, then nuclear fusion begins and a star is born.
Explanation:
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Answer:
Some elements have variable valencies because of the different electronic configurations. An atom of an element can sometimes lose more electrons than are present in its valence shell i.e. loss from the penultimate shell and hence exhibit more than 1 or variable valency.
Explanation:
Hope it helps.
Answer:
1. 0.138g of valium would be lethel in the woman
2. 125mg/min is the drip of the patient
Explanation:
1. In a body, an amount of Valium > 1.52mg / kg of body weight would be lethal.
A person that weighs 200lb requires:
200<u>lb</u> × (453.6<u>g</u> / <u>1lb</u>) × (1kg / 1000<u>g</u>) = <em>90.72kg (Weight of the woman in kg)</em>
90.72kg × (1.52mg / kg) =
137.9mg ≡
<h3>0.138g of valium would be lethel in the woman</h3>
2. The IV contains 1.5g = 1500mg/mL.
If the patient is receiving 5.0mL/h, its rate in mg/h is:
5.0<u>mL</u>/h × (1500mg/<u>mL</u>) = 7500mg/h
Now as 1h = 60min:
7500mg/<u>h</u> × (1<u>h</u> / 60min) =
<h3>125mg/min is the drip of the patient</h3>
Answer: Antoine Lavoisier
