Hydrofluoric acid is listed in Table 10 as a weak acid; therefore, it is not very dangerous to handle. False.The correct litmus test for an acid is<span>: blue litmus turns red. Choose the strongest acid. Choose the strongest acid. A characteristic of acids is that they react with metals to: release hydrogen gas. When acids react with .</span>
Answer:
SUBSTANCES
Explanation:
According to this question, Jasmine is conducting an experiment in order to see how much temperature change occurs when three different substances are heated. Based on this experiment, the INDEPENDENT VARIABLE, which is the variable that is changed or manipulated is SUBSTANCES.
A controlled experiment is an experiment where all other variables except the INDEPENDENT VARIABLE is kept the same or unchanged. The independent variable is the only variable allowed to change, which in this case is the SUBSTANCES USED.
Answer:
a. 2. The reagents were added to a round bottom flask prior to the reaction being heated under reflux.
b. 3. The solution of benzoic acid and methanol was heated in a steam bath
c. 4. The reaction mix was washed with sodium carbonate solution.
d. 1. Magnesium sulfate is added to the dichloromethane layer before the solvent is distilled off.
Explanation:
Fisher esterification is an equilibrium process. There are unreacted carboxylic acids in the reaction mix which are weak acids and they neutralize into aqueous solution. Magnesium sulfate is drying agent there water should be removed from dichloromethane solution before the solvent is distilled off.
Answer:
When a boy smells the aroma coming from the pot on the stove is actually detecting the chemicals coming from the air which comes from hot food that dissolves in the mucus present in the nasal cavity that carries tiny hairs made up of the nerve fibers that absorb these chemicals and excite or stimulate the olfactory receptors.
Various types of a distinct aroma or smell lead to a specific combination of the olfactory cells to make a specific smell. These combination patterns transported to the olfactory bulb along axons; a long extended neuron.
The sensory patterns or information encoding the smell of food present in the pot reaches the primary olfactory cortex in the brain, which is present on the anterior surface of the temporal lobe, and decodes accordingly.
In this question we are asked to round off the figure 0.02056 to three significant figures.
We are given with four options to chose best out of four
a) 0.0205
b) 0.0206
c) 0.021
d) 0.020
In this question, option (b) is correct i.e. 0.0206.
There are four significant rules, we should keep in mind during round off:
- Non-zero digits are so significant
- Zeros between two non-zero digits are significant
- Leading zeros are not significant
- Trailing zeros are important only if the number contains a decimal point
To know more about Round off:
brainly.com/question/24234983
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