Questions posted in Chemistry

What is the chemical symbol for nitrogen and oxygen?

N2 and O2

hope it helps

ANSWERED AT 28/02/2020 - 04:26 PM


QUESTION POSTED AT 28/02/2020 - 04:26 PM

A certain vinegar is 6.02% acetic acid (hc2h3o2, by mass. how many grams of acetic acid are contained in a 355 ml bottle of vinegar. assume a density of 1.01 g/ml.

First, determine the amount of vinegar in grams by multiplying the volume by the density. That is,
                                        mass = (355 ml) x (1.01 g/mL) = 358.55 g
Then, multiply the calculated mass above by the decimal equivalent of the given percentage above. 
                      amount of acetic acid = (358.55 g)(0.0602) = 21.58 g

ANSWERED AT 28/02/2020 - 04:11 PM


QUESTION POSTED AT 28/02/2020 - 04:11 PM

What makes the tea with milk and lemon curdle?

Answer:

The acidic nature of the lemon

Explanation:

ANSWERED AT 28/02/2020 - 04:06 PM


QUESTION POSTED AT 28/02/2020 - 04:06 PM

Nuclear energy is produced when scientists force uranium (U) atoms to break apart. With this in mind, examine the list below. If scientists were to break apart each of the items on the list, which items would still be classified in the same way? Which items would be classified differently? • atoms • elements • compounds • molecules • matter

Answer:

Compound.

Explanation:

A compound is a made up of two or more than two different elements. It can be broken down into smaller molecules.Elements are combined to form a compound by chemical bonding like ionic bonding and covalent bonding.

Different compounds of different elements can be broken down into the chemical reaction called decomposition reaction. For example:

Using electrolysis, we can break down water into its elements hydrogen and oxygen.    

ANSWERED AT 28/02/2020 - 04:06 PM


QUESTION POSTED AT 28/02/2020 - 04:06 PM

What is the net ion charge of beryllium? +2 -2 +1 -1

Answer:

+2

Explanation:

ANSWERED AT 28/02/2020 - 04:01 PM


QUESTION POSTED AT 28/02/2020 - 04:01 PM

An atom of an element has 28 innermost electrons and 7 outermost electrons. In which period of the Periodic Table is this element located? 1. 5 2. 2 3. 3 4. 4

Answer: The given element belongs to Period 4.

Explanation:

We are given:

Number of innermost electrons = 28

Number of outermost electrons = 7

Total number of electrons = 28 + 7 = 35

Electronic configuration is defined as the representation of electrons around the nucleus of an atom.

Number of electrons in an atom is determined by the atomic number of that atom.

The electronic configuration of the element having atomic number '35' is:  1s^22s^22p^63s^23p^64s^23d^{10}4p^5

To identify the period, we look at the highest occupied principle quantum number which is 'n'. Here, the value of highest occupied shell or 'n' is 4.

Hence, the given element belongs to Period 4.

ANSWERED AT 28/02/2020 - 03:57 PM


QUESTION POSTED AT 28/02/2020 - 03:57 PM

What is the most widely used base in industry? What are it's main uses?

There are three potential answers, ammonia, lime, and sodium hydroxide. These three vary in usage depending on the setting and indusry. For instance, ammonia is widely used as a fertilizer and refrigerant.  Thank you for your question. Please don't hesitate to ask in Brainly your queries. 

ANSWERED AT 28/02/2020 - 03:51 PM


QUESTION POSTED AT 28/02/2020 - 03:51 PM

What happens to the temperature of water between the time ice melts and water boils (this is partially quoted from a question)? Also, what change occurs in temperature after water starts boiling (this is also from a booklet)? Thank you and please explain your thoughts. This is based on the phase changes of water, and you should refer to a graph on the phase changes of water.

Your first statement is very ambiguous so I will give it the best shot as to what you are saying.
The temperature, between the point of ice melting and water boiling, is increasing as water is in its liquid state.
Now during a phase change, or while the water is boiling, the temperature remains constant because the energy being added is being consumed to complete the phase change.
But if you're looking at the phase change graph, the points of positive slopes, are moments when energy is increasing as the water, in whatever state, is increasing. But when the slope of the graph is 0, the water is changing phases and the temperature remains constant! I hope I explained that so you could understand it, and I hope this helps you!

ANSWERED AT 28/02/2020 - 03:47 PM


QUESTION POSTED AT 28/02/2020 - 03:47 PM

What chemical is in plastic bottle and how it affect humans?

BPA, or bisphenol A, is in most plastics and it is toxic to humans because it can bind to the estrogen hormone and greatly alter your body's natural functions from there. It can also bind to your thyroid hormone.

ANSWERED AT 28/02/2020 - 03:44 PM


QUESTION POSTED AT 28/02/2020 - 03:44 PM

Determining missing genotypes

What are the genotypes

ANSWERED AT 28/02/2020 - 03:42 PM


QUESTION POSTED AT 28/02/2020 - 03:42 PM

The modern model of the atom used today is the Plum Pudding model. true or false

That would be false.

ANSWERED AT 28/02/2020 - 03:42 PM


QUESTION POSTED AT 28/02/2020 - 03:42 PM

How can a molecule have a momentary dipole?????

Here is my answer to your question  it is by a random momentary clustering of electrons in one particular point of an atom or molecule that is how a molecule have a momentary dipole. AND.... hope u enjoy my answer.

ANSWERED AT 28/02/2020 - 03:41 PM


QUESTION POSTED AT 28/02/2020 - 03:41 PM

How do you draw molecular compound structures? Example: C2H2

It's hard to describe how to draw these compounds. However, I will try my best using the example provided. The example provided would look like this H-C(triple bond)C-H. First it is important to know how many electrons you are working with. In this case there are ten electrons. 8 from carbon and 2 from hydrogen. After you know this, you can draw the structure. Each carbon atom needs an octet or eight atoms surrounding it. Creating a triple bond with the other carbon and a single bond with one hydrogen atom allows for this to happen. It takes practice to master drawing structures but with time it gets easier! I hope this helped! 

ANSWERED AT 28/02/2020 - 03:39 PM


QUESTION POSTED AT 28/02/2020 - 03:39 PM

Discuss, in detail, three things that we can learn from fossils. (15 points)

What used to exist before humans.
Years and age of whatever the fossils may be
I'm not sure about the other sorry :(

ANSWERED AT 28/02/2020 - 03:33 PM


QUESTION POSTED AT 28/02/2020 - 03:33 PM

When you use the claw of a hammer to remove a nail , what type of simple machine are you using

You'd be using a wedge.

ANSWERED AT 28/02/2020 - 03:29 PM


QUESTION POSTED AT 28/02/2020 - 03:29 PM

How do modern tools such as Doppler radar satellite weather balloons and computers help meteorologist understand weather

They send accurate data by using sensors and can often predict future precipitation and weather

ANSWERED AT 28/02/2020 - 03:29 PM


QUESTION POSTED AT 28/02/2020 - 03:29 PM

How do modern tools such as Doppler radar satellite weather balloons and computers help meteorologist understand weather

They give information about wheatger patterns which th use to pedict the wheather

ANSWERED AT 28/02/2020 - 03:27 PM


QUESTION POSTED AT 28/02/2020 - 03:27 PM

What kind of instrument is this and explain the details what it measures

I believe it measures the pressure in the atmosphere. Not positive on the name...barometric pressure gauge? 

ANSWERED AT 28/02/2020 - 03:27 PM


QUESTION POSTED AT 28/02/2020 - 03:27 PM

All of the following are conductors of electricity except

Rubber it's not a conductor

ANSWERED AT 28/02/2020 - 03:25 PM


QUESTION POSTED AT 28/02/2020 - 03:25 PM

All of the following are conductors of electricity except

What are the choices?

ANSWERED AT 28/02/2020 - 03:24 PM


QUESTION POSTED AT 28/02/2020 - 03:24 PM

What is relief and how does it affect soil formation

S is for soil,cl (sometimes c) represents climate,o organisms including humans,r relief,p parent material, or lithology, andt time.

ANSWERED AT 28/02/2020 - 03:24 PM


QUESTION POSTED AT 28/02/2020 - 03:24 PM

What does CIORPT stand for what factors make up CIORPT

CLORPT is a mnemonic for Hans Jenny's equation for soil formation.  CLORPT Stands for Climate Organisms Relief Parenet material Time

ANSWERED AT 28/02/2020 - 03:23 PM


QUESTION POSTED AT 28/02/2020 - 03:23 PM

What is the empirical formula for a compound that is a 83.7% carbon and 16.3% hydrogen

The empirical formula for a compound that is a 83.7% carbon and 16.3% hydrogen is CH2

ANSWERED AT 28/02/2020 - 03:23 PM


QUESTION POSTED AT 28/02/2020 - 03:23 PM

Write the symbol for every chemical element that has atomic number less than 74 and atomic mass greater than 173.8u

You should be able to locate them on the periodic table as long as you know which part the atomic number is and which part the atomic mass is.

ANSWERED AT 28/02/2020 - 03:22 PM


QUESTION POSTED AT 28/02/2020 - 03:22 PM

A cell's ____________ contains all the information necessary to direct the cell.

The dna contains all the information.

ANSWERED AT 28/02/2020 - 03:21 PM


QUESTION POSTED AT 28/02/2020 - 03:21 PM

How does the scientific meaning of a theory differ from its everyday sense?

A scientific theory is a scientific work, which describes a system behind observations and makes predictions for future observations

ANSWERED AT 28/02/2020 - 03:17 PM


QUESTION POSTED AT 28/02/2020 - 03:17 PM

What would be an advantage and a disadvantage to using litmus as a titration indicator??? Please Help!!!

To indicate whether the elements is basic or acid by changing of colour.(advantage)
can give out bad gas which can cause suffocate to the people.(disadvantage).

ANSWERED AT 28/02/2020 - 03:13 PM


QUESTION POSTED AT 28/02/2020 - 03:13 PM

What chemicals are released by burning oil, and how are they harmful?

Carbon dioxide, carbon monoxide, lead, nitrogen oxides, particulate matter, polycyclic aromatic hydrocarbons, sulfur dioxide , and volatile organic compounds.
They are harmful to human health.

ANSWERED AT 28/02/2020 - 03:11 PM


QUESTION POSTED AT 28/02/2020 - 03:11 PM