The answer is A....... brainiest plz?
Answer:-
Water is highly ordered. In water each oxygen atom is connected to others around it through hydrogen bonding via bridging hydrogen atoms. When a salt like NaCl is dissolved, some of these Hydrogen bonds break.
When a salt like NaCl dissolves in water, the NaCl breaks in to ions Na+ and Cl-.
The water molecules now surround these ions.
The slightly negative oxygen end of water molecule gets near the Na+, while the slightly positive Hydrogen of water molecule gets near the Cl-.
So before salt sample dissolve, the water molecules were highly ordered due to hydrogen bonding. Now after salt dissolve there is a decrease in order and thus an increase in disorder of the water molecules.
Due to increase in disorder, entropy which is a measure of disorder increases. Since entropy increases, delta S for the process is positive.
1. The reaction is exothermic.
2. I know this because the delta H is a negative number. (-802.4 kJ)
3. This means that this reaction releases heat.
The correct answer is B. An observation
Explanation:
An observation is defined as a statement or conclusion you made after observing or measuring a phenomenon, this includes statements based on precise instruments. For example, if you conclude a plant grows 2 inches every month by measuring the plant during this time, this is classified as an observation. The conclusion of the student is also an observation because he concludes this after analyzing the volume of the water in the cylinder through the lines in the graduated cylinder, considering the water is just in the middle of 100 mL and 200 mL which indicates there are 150 mL of water.
Answer:
49.4 mol Oxygen
Explanation:
Mg(NO3)2 ----- 6 O
1 mol 6 mol
8.24 mol x mol
x = 8.24*6/1 = 49.44 mol ≈ 49.4 mol Oxygen