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Veseljchak [2.6K]
3 years ago
13

Which statement about exothermic reactions are true?

Chemistry
1 answer:
Hatshy [7]3 years ago
7 0

Answer:

It is either the third or fourth statement.

Explanation:

This is because exothermic reactions give off heat.

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Josh drives her scooter 7 km north. she stops for lunch and then drives 5 km east. what distance does she cover? what was her di
weqwewe [10]

Explanation:

Find the motion diagram attached for the illustration:

Distance is the length of path traveled from the start to the finish. In measuring distance, we wall through the path from start to the finishing point. Distance is a scalar magnitude that has magnitude but no direction.

Displacement is distance that is taken between the start and finishing point. It is a vector quantity that has magnitude and measures direction.

To find the distance;

Distance = 5km + 7km = 12km

Displacement:

 Using pythagoras theorem;

   Displacement = √7² + 5² = 8.6km

 Direction:

    sin(bearing ) = \frac{5}{8.6}  = 0.5814

   bearing = arcSin 0.5814 = 035.6°

Displacement is 8.6km in a direction 035.6°

learn more:

Displacement brainly.com/question/6123316

#learnwithBrainly

6 0
3 years ago
If the temperature and amount of gas stays constant, what will happen to the pressure of a gas if the volume of the container de
devlian [24]
If temperature is held constant, the equation is reduced to Boyle's law. Therefore, if you decrease the pressure of a fixed amount of gas, its volume will increase. However, if you were to maintain a constant volume while decreasing pressure, the temperature would also have to decrease.
4 0
2 years ago
1. At room temperature, air is usually a (solid, liquid, gas).​
kirza4 [7]
At room temperature the air is Gas
3 0
2 years ago
What is one advantage of doing a feild experiment instead of a laboratory experiment
Ber [7]

Answer:

  Field experiments can often have the potential to give scientists opportunities that are not possible in a lab setting.

Explanation:

  Having people "act natural" in a lab setting is impossible to truly achieve, as we all know what happens to our mental state and behavior when we are being actively observed. This is also especially helpful when conducting wildlife research, as there are a myriad of different things influencing animal and plant behavior that would be nigh impossible to recreate perfectly in a controlled lab setting.

  Field research can have its disadvantages as well, as it is very hard to only have one thing change (make an independent variable) in a wild environment with ever-changing weather, social effects, etc. Also, you, as the researcher, as causing an impact on the very location that you are observing, which can alter your results in unpredictable ways.

  The thing to remember is that each type of study has its advantages and disadvantages; if they didn't, then we'd all do the same type of research! You have to weigh your research options and figure out which one works best for your situation :)

3 0
2 years ago
Among the alkali earth metals, the tendency to react with other substances
tatyana61 [14]
Answer: option <span>A) increases from bottom to top within the group.

Explanation:

</span>It is a known trend that the metallic character of the elements increase from let to right and from top to bottom.

The greater the metallic character the greater the reactivity of the metal.

So, the elements of the columns 1 and 2 are the most reactive metals and among them the elements at the bottom are yet more reactive.

<span>The higher reactivity of the metals that are lower in the periodic table is attributed to the greater total number of electrons.

The greater the total number of electrons the more reactive the metals as their outermost electrons (the valence electrons which are those that react) are located further from the nucleus and therefore they are held less strongly, which makes them react more easily.</span>
5 0
3 years ago
Read 2 more answers
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