Answer:
the strength of gravitational force between two objects depends on two factors,mass and distance. the force of gravity the masses exert on each other. if one of the masses is doubled, the Force of gravity between the object is doubled. increases the force of gravity decreases.
The sample must be sufficiently soluble (fig. 2) to yield an NMR spectrum. For 1H and 1H observed NMR, it is recommended to dissolve between 2 and 10 mg in between 0.6 and 1 mL of solvent so that the sample depth is at least 4.5 cm in the tube (fig. 3).
The answer would be D carbon dioxide
Answer:
See explanation
Explanation:
When a beaker of ethanoic acid is placed in the refrigerator, its temperature drops and the vessel feels cool.
Now, when we mix ethanoic acid and sodium carbonate, an endothermic reaction occurs, fizzing is observed as carbon dioxide is given off and heat is lost to the surroundings causing the reaction vessel to feel cool to touch.
The difference between putting ethanoic acid in the refrigerator and adding sodium carbonate to the solution is that, in the former, no new substance is formed. The substance remains ethanoic acid when retrieved from the refrigerator. In the later case, new substances are formed. The substance is no more ethanoic acid because a chemical reaction has taken place.