Answer:
a. positive
b. negative
c. positive
d. negative
Explanation:
In a exothermic reaction, heat is written as a product (del H is negative), whereas in an endothermic reaction heat is written on the reaction side (del H is positive).
For a, it is endothermic process. We know this because to go from solid to liquid you need to put energy into the system. When we put energy into a chemical system it is said to be an endothermic reaction.
For b, it is exothermic reaction. This is because you have to lose the extra energy to go from less ordered states (gas) to more ordered state (liquid). Gas is less ordered because its molecules are freely moving and such. Another way of thinking about this question is just putting the heat on product side and think if I was going in reverse direction I would put heat in product because I would need to add heat to liquid to turn to gas (and if heat is added to product side we know its exothermic). Two ways of thinking whichever you prefer.
The rest have similar explaination.
I am going to be honest i’m good at chemistry but i need the point cause i need help on my history work
Was there supposed to be a picture?
Answer:
Mescarinic and Nicotinic
Explanation:
Postganglionic fibers can be present in both sympathetic and parasympathetic divisions, their main difference resides in how in the sympathetic division the postganglionic fibers are adrenergic and use norepinephrine (noradrenalin) as a neurotransmitter, in the parasympathetic division, on the other hand, fibers are cholinergic and use acetylcholine as a neurotransmitter, the<em> postganglionic neurons of sweat glands release acetylcholine for the activation of muscarinic receptors, another kind of receptor for acetylcholine are nicotinic receptors </em>that act as transmembrane sodium/potassium channels, while muscarinic receptors need to act through intracellular proteins.
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Answer:
The speed of the turtle is 9.41 centimeters per second.
Explanation:
Speed of small turtle = 566 furlong/fortnight
1 furlong = 20,116.8 cm
1 fortnight = 1,209,600 seconds
Speed of small turtle in centimeter per seconds:
The speed of the turtle is 9.41 centimeters per second.
Explanation: