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Alexandra [31]
3 years ago
9

What is an observation? what is an observation?

Chemistry
1 answer:
allsm [11]3 years ago
3 0

Answer:

Definition: a statement based on something one has seen, heard, or noticed

Explanation:

In my own words it would be something you would have seen or heard.

For example you add salt to a glass of water and stirred it. An observation would be that you watched the salt dissolve in the water.

You might be interested in
Describe three skills people use to conduct scientific investigations
Kipish [7]
Observations, surveys, and models.
6 0
3 years ago
You are using a ruler to measure the width of a test tube. The edge of the test tube is between 3 cm and 4 cm marks. if centimet
Arada [10]

Answer:

A) 3.6 cm

Explanation:

Accuracy comes down to how precisely you can read the length on a given scale. Here since the smallest increment is centimeter, we can go only one decimal beyond to estimate. This is because you can usually estimate to only one decimal place beyond the closest marks on any measuring.

So, the answer should be 3.6 cm.

Here's a document that explains it well: https://www.auburn.wednet.edu/cms/lib03/WA01001938/Centricity/Domain/1360/1_Uncertainty.pdf

Hope that's right!

5 0
2 years ago
What is the Molarity of a solution of HNO3 if it contains 12.6 moles in a<br> 0.75 L solution? *
Korolek [52]

Answer:

M = 16.8 M

Explanation:

<u>Data:</u> HNO3

moles = 12.6 moles

solution volume = 0.75 L

Molarity is represented by the letter M and is defined as the amount of solute expressed in moles per liter of solution.

M=\frac{moles}{solution volume}

The data is replaced in the given equation:

M=\frac{12.6 mol}{0.75L}=16.8\frac{mol}{L}

7 0
3 years ago
Read 2 more answers
If 8.500 g CH is burned and the heat produced from the burning is added to 5691 g of water at 21 °C, what is the final
mojhsa [17]

The final temperature = 36 °C

<h3>Further explanation</h3>

The balanced combustion reaction for C₆H₆

2C₆H₆(l)+15O₂(g)⇒ 12CO₂(g)+6H₂O(l)  +6542 kJ

MW C₆H₆ : 78.11 g/mol

mol C₆H₆ :

\tt \dfrac{8.5}{78.11}=0.109

Heat released for 2 mol C₆H₆ =6542 kJ, so for 1 mol

\tt \dfrac{0.109}{2}\times 6542=356.539~kJ/mol

Heat transferred to water :

Q=m.c.ΔT

\tt 356.539=5.691~kg\times 4.18~kj/kg^oC\times (t_2-21)\\\\t_2-21=15\rightarrow t_2=36^oC

3 0
3 years ago
Name any <br>three kinds of mixtures with example​
sleet_krkn [62]

Answer:

Here are a few more examples:

Smoke and fog (Smog)

Dirt and water (Mud)

Sand, water and gravel (Cement)

Water and salt (Sea water)

Potassium nitrate, sulfur, and carbon (Gunpowder)

Oxygen and water (Sea foam)

Petroleum, hydrocarbons, and fuel additives (Gasoline)

Heterogeneous mixtures possess different properties and compositions in various parts i.e. the properties are not uniform throughout the mixture.

Examples of Heterogeneous mixtures – air, oil, and water, etc.

Examples of Homogeneous mixtures – alloys, salt, and water, alcohol in water, etc.

Explanation:

8 0
3 years ago
Read 2 more answers
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