1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Sonja [21]
3 years ago
9

What trends were seen in medeleevs periodic table

Chemistry
1 answer:
Paraphin [41]3 years ago
8 0

Answer:

groups are based on how many electrons to become stable

Explanation:

You might be interested in
When an aqueous solution of magnesium nitrate is mixed with an aqueous solution of potassium carbonate, ____________.?
spin [16.1K]
  <span>Ca(NO3)2 + Na2CO3 = CaCO3 + 2NaNO3 
Yes a precipitate of Calcium Carbonate is formed since it is insoluble in water. 
Mol Wt of Calcium Nitrate is 164. And that of Calcium Carbonate is 100. 
One mole of Calcium Nitrate produces one mole of Calcium Carbonate. 
i.e. 164 gms will produce 100gms of precipitate 
So, 1.74gms of Calcium Carbonate will be obtained from 2.85gms Calcium Nitrate present in the original solution.</span>
3 0
3 years ago
How many carbon atoms are represented in the formula for CaMg3(CO3)4​
Galina-37 [17]
The formula is for 1 Calcium, 3 Magnesium, 4 Carbon, & 12 Oxygen. The 4 after the parenthesis of (CO3) distributes to each element.

Answer : There are 4 Carbon atoms in the formula.
3 0
2 years ago
Consider the following weak acids and their Ka values: Acetic Acid Ka = 1.8×10^−5 Phosphoric Acid Ka = 7.5×10^−3 Hypochlorous Ac
vfiekz [6]

Answer:

a. Phosphoric Acid

b. Acetic Acid

c. Hypochlorous Acid

Explanation:

A buffer works when the pH of this one is in pKa ± 1. That means, to find which buffer system works in some pH you need to find pKa:

pKa = -log Ka

<em>pKa Acetic acid:</em>

-log1.8x10⁻⁵ = 4.74

<em>pKa phosphoric acid:</em>

-log7.5x10⁻³ = 2.12

<em>pKa hypochlorous acid:</em>

-log3.5x10⁻⁸ = 7.46

a. For a pH of 2.8 the best choice is phophoric acid because its effective range is: 1.12 - 3.12 and 2.8 is between these values.

b. pH 4.5. Acetic acid. effective between pH's 3.74 - 5.74

c. pH 7.5. Hypochlorous acid that works between 6.46 and 8.46

7 0
3 years ago
What is the percent composition of hydrogen in NH4HCO3?
Readme [11.4K]
To find the Percent Composition of an atom, you use this formula:
Mass of element in the compound you're studying on ( in this case it's 5 since there is 5 Hydrogens) over the mass of the compound (which is here 79), Multiplied by 100 since you want a percent. 
So we get: 
\frac{5}{79} * 100
So you get about: 
0.063 * 100
6.3

So, the percent composition of Hydrogen in NH4HCO3 is 6.3%

Hope this Helps! :D


7 0
3 years ago
Read 2 more answers
Which would exert more pressure on the floor, a 100kg man wearing snow shoes or a 60kg woman wearing high heels? PLEASE EXPLAIN
iris [78.8K]

Pressure can be defined as the force acting on a perpendicular surface per unit area.

Force exerted by a man of mass 100 kg wearing snow shoes = m.a

Where m = mass of the man = 100 kg

a = acceleration due to gravity= 9.8 m/s^{2}

Force exerted by the man of mass 100 kg = 100 kg(9.8 m/s^{2}) = 980 N

Force exerted by woman of mass 60 kg = 60 kg(9.8 m/s^{2}) = 588 N

Force exerted by 100 kg man is greater than that exerted as 60 kg woman. The area on which this force is acting determines the pressure. Pressure is inversely proportional to the area on which the force acts. Therefore, the pressure exerted by 100 kg man wearing snow shoes is less than the pressure exerted by a 60 kg woman woman wearing high heels as the force acts over a larger area when the man wears snow shoes when compared to the force exerted over a smaller area in case of the woman wearing high heels.

5 0
2 years ago
Other questions:
  • Why are cirrocumulus clouds sometimes called mackerel clouds
    14·1 answer
  • Balance the following equation by inspection: <br> Cu + HNO3 --&gt; Cu(NO3)2 + H2O +NO
    12·2 answers
  • When a mixture of glucose 6-phosphate and fructose 6-phosphate is incubated with the enzyme phosphohexose isomerase, the final m
    11·2 answers
  • For heat transfer purposes, a standing man can be modeled as a 30-cm-diameter, 175-cm-long vertical cylinder with both the top a
    13·1 answer
  • Value of an extensive property
    8·1 answer
  • What mass of hydrochloric acid (in grams) can 2.7 g of sodium bicarbonate neutralize? (Hint: Begin by writing a balanced equatio
    5·1 answer
  • The human body receives sensory information from its surroundings. The body knows when food is warm or cold and whether an objec
    10·1 answer
  • If you have 3.5 L of He to blow up balloons... at STP...
    5·1 answer
  • What is the most reactive metal in Period 4 of the periodic table?
    14·1 answer
  • How to do Lewis structure for Al?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!