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pychu [463]
2 years ago
5

I NEED HELP FAST!!!!! Can you tell me about the development of the periodic table??? I have a DBA in a few minutes and I don't k

now!!! Please use easy to understand answers 'cause I'm a little under the weather.
Chemistry
1 answer:
weqwewe [10]2 years ago
5 0
Dimitri Mendeleev was the first to put elements together on a table. He knew there were elements missing but he noticed a trend in some of the elements known at the time. Sodium, Lithium and other alkali metals all have the same properties so he put them under the same column and created other columns with similar attributes (Halogens, Noble gases, Alkaline earth metals). Over the years, new elements were discovered and put into the rough outline that Mendeleev created.

I hope that is about what you wanted. 
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Draw the structure corresponding to the common name α−chloro−β−methylbutyric acid
uysha [10]

Structure of a-chloro-b-methylbutyric acid (2-chloro-3-methylbutyric acid is attached below.


The structure was drawn using following information.


1) First, the parent chain was identified. The parent chain is containing four carbon atoms, also, this chain belongs to carboxylic acid as the compound name ends with Butyric acid i.e. butyr (Butane) -ic acid (carboxylic acid).


2) Secondly, the positions of substituents were assigned by using the rule which sates that the numbering in carboxylic acid must satrt from the carbonyl carbon. Therefore, the carbon which is attached to carbonyl carbon is named as alpha (2nd position) and carbon next to alpha carbon is named as beta carbon (3rd position). Hence, we add chlorine atom on 2nd carbon next to carbonyl group and methyl group at 3rd carbon with respect to carbonyl carbon.

6 0
3 years ago
Read 2 more answers
Type the correct answer in the box. Express your answer to two significant figures. An industrial vat contains 650 grams of soli
SashulF [63]

88.98 %

The Balance Chemical Equation is as follow,

                                  2 HCl + Pb(NO₃)₂     →    2 HNO₃ + PbCl₂

According to equation,

          331.2 g (1 mole) Pb(NO₃)₂ produces  =  278.1 g (1 mole) PbCl₂

So,

                 870 g of Pb(NO₃)₂ will produce  =  X g of PbCl₂

Solving for X,

                     X  =  (870 g × 278.1 g) ÷ 331.2 g

                     X  =  730.5 g of PbCl₂

Therefore,

               Theoretical Yield =  730.5 g

Also as given,

                Actual Yield =  650 g

So using following formula for percentage yield,

                        %age Yield  =  (Actual Yield / Theoretical Yield) × 100

Putting values,

                        %age Yield  =  (650 g / 730.5 g) × 100

                        %age Yield  =  88.98 %

Brianliest please and thank you.

4 0
3 years ago
The molar mass of the metal oxide M2O is 231.74 g/mol. What is the molar mass of the chloride of this metal?
Semenov [28]
The molar mass of the M2O = 2(molar mass of M) + molar mass of oxygen
Molar mass of oxygen = 16
Therefore:
231.74 = 2(molar mass of M) + 16
215.74 = 2*molar mass of M
molar mass of M = 107.87 grams

Now, from the given formula, we can notice that the metal M is monovalnet and we know that chlorine is monovalent as well.
Therefore, the compound formed will be: MCl
molar mass of chlorine = 35.5 grams
Therefore,
molar mass of MCl = 107.87 + 35.5 = 143.37 grams
5 0
3 years ago
Science quiz help plssssss
xxMikexx [17]

Answer:

3. It should restate the question

4. a controlled experiment

5. if I freeze a tennis ball then it will not bounce as high

Explanation:

6 0
2 years ago
Why isn't the atomic mass of most of the elements on the Periodic Table an integer (not a decimal)?
elena55 [62]

Answer:

Atomic mass is never an integer number for several reasons

4 0
3 years ago
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