Who was known as the ‘laughing philosopher’?
Answer:
Democritus
Explanation:
Answer:
Democritus
Explanation:
They called him that because of his cheerfulness and how he treated people .
Hoped I helped-
Sleepy-
which iconic compound is used as a building material?
Answer:
Magnesium oxide is an ionic compound that can be used as a building material. MO2 is actually a raw material that used in producing cement for building houses, buildings, and other constructions.
Explanation:
28.The chemical formula of a compound indicates
the source of the elements in the compound.
b. how elements are joined in the compound.
the alchemy symbols for the elements in the compound.
d. the relative proportions of the elements in the compound.
Answer:
d. the relative proportions of the elements in the compound.
Explanation:
The chemical formula of a compound indicates the relative proportions of the element in the compound.
The chemical formula of a compound is a representation which shows all the elements therein and the mole relationship between them expressed as subscripts. For example HCl, contains one mole of hydrogen and 1 mole of Cl.Which problem that the most scientists believe is partly caused by carbon dioxide?
Answer:
Climate change
Explanation:
Climate change is primarily a problem of too much carbon dioxide (CO2) in the atmosphere. This carbon overload is caused mainly when we burn fossil fuels like coal, oil and gas or cut down and burn forests
How many milliliters of alcohol are present in 720 mL of brandy?
Answer:
Answer : The volume of water and alcohol present in 675 mL of this solution is 405 mL and 270 mL respectively.
Explanation: As we are given that 40.0 % (v/v) alcohol solution. That means, 40.0 mL of alcohol present in 100 mL of solution.
Now we have to calculable the volume of alcohol in 675 mL solution.
As 100 mL of solution contains 40.0 mL of alcohol
So, 675 mL of solution contains alcohol
Thus, the volume of alcohol = 270 mL
Now we have to calculate the volume of water.
The volume of water = Volume of the solution - Volume of alcohol
Volume of water = 675 mL - 270 mL
The volume of water = 405 mL
Thus, the volume of water = 405 mL
Hence, the volume of water and alcohol present in 675 mL of this solution is 405 mL and 270 mL respectively.
The 720mL of an 80-proof brandy which is 40.0% (v/v) ethyl alcohol, contains 288 mL of ethyl alcohol.
What is volume/volume percentage?The Percent solutions can be expressed in the form of volume/volume percentage, weight/volume percentage, or, weight/weight percentage. The concentration of the solution in percentage is calculated as the fraction of the weight or volume of the solute related to the total weight or volume of the solution.
The solution where concentration requires to be represented in volume percent (v/v%) when the solute is a liquid phase. It is also applicable to the numerator and the denominator in volume units and is called volume/volume percent.
Volume percentage = (Volume of solute/volume of solution) x 100
The given brandy has ethyl alcohol the v/v % is 40 %.
It means the 40 ml of ethyl alcohol is present in the 100ml of brandy
Given the volume of brandy = 720 ml
Volume of ethyl alcohol in 720 ml of brandy = (40/100)×720 = 288 ml
Therefore, 288 ml of ethyl alcohol is present in 720 ml of brandy which is 40.0% (v/v) ethyl alcohol.
Learn more about volume/volume percentage, here:
https://brainly.com/question/13558694
#SPJ2
Your question is incomplete, but most probably complete question was,
An 80 proof brandy is 40.0% (v/v) ethyl alcohol. The "proof" is twice the percent concentration of alcohol in the beverage. How many milliliters of alcohol are present in 720 mL of brandy?
How many moles of H are present in 3 moles of carbon trihydride?
Answer:
4moles of carbon trihydride
how does conc.H2SO4 reacts with sugar?
How long is a wave traveling at 120 m/s if it has a frequency of 30 Hz?
Answer:
4 m
Explanation:
HELP!!! 30 POINTS!!!
Explanation:
[tex]periodic \: law[/tex]
It's correctAnswer
you already got it
Explanation:
___ The energy of moving particles.
a. Chemical Energy
b. Radiant Energy
c. Mechanical Energy
What is the % of H20 in Sodium carbonate decahydrate, Na2CO3 • 10H2O
Answer:
Element Symbol # of Atoms
Sodium Na 2
Cobalt Co 3
Hydrogen H 20
Oxygen O 10
Explanation:
Please help me I. Eg you
Answer:
fehrf beviubeibchvbiscv kie v sjb rlj jsrubw
Explanation:
22. In 4f12, the 12 stands for the
The 12 stands for the number of electrons that fill the f orbital
Further explanationIn an atom there are levels of energy in the shell and sub shell
This energy level is expressed in the form of electron configurations.
Writing electron configurations starts from the lowest to the highest sub-shell energy level. There are 4 sub-shells in the shell of an atom, namely s, p, d and f. The maximum number of electrons for each sub shell is
• s: 2 electrons
• p: 6 electrons
• d: 10 electrons and
• f: 14 electrons
4f¹² :
4 : number of shell
12 : the number of electrons that fill the f orbital
Calculate the heat evolved for the reaction of 2.50 L of B2H6 with 5.65 L of Cl2 according to the following reaction. Both reactant gases are initially at STP
B2H6(g) + 6 Cl2(g) —> 3 BCl3(g) + 6HCl(g) Delta H = -1396 kJ
The heat evolved with the [tex]\rm B_2H_6[/tex] has been 58.637 kJ.
From the balanced chemical equation, 1 mole of [tex]\rm B_2H_6[/tex] reacts with 2 moles of Chlorine to give 3 moles of boron chloride and 6 moles of HCl,
The chlorine has been required in double the quantity of boron hexahydride.
The moles of Chlorine has been the limiting reactant.
The chlorine that has been responsible for the reaction with [tex]\rm B_2H_6[/tex] will be:
6 Chlorine = 1 [tex]\rm B_2H_6[/tex]
5.65 L Chlorine = [tex]\rm \dfrac{5.65}{6}[/tex]
5.65 L Chlorine = 0.942 L [tex]\rm B_2H_6[/tex].
The moles of [tex]\rm B_2H_6[/tex] can be calculated as:
1 Mole = 22.4 L
Moles of [tex]\rm B_2H_6[/tex] in 0.942 L = 0.042 mol.
The heat evolved for 1 mole [tex]\rm B_2H_6[/tex] has been -1396 kJ.
The heat evolved for 0.042 mol [tex]\rm B_2H_6[/tex] = 0.042 × -1396 kJ.
The heat evolved = 58.637 kJ.
The heat evolved with the [tex]\rm B_2H_6[/tex] has been 58.637 kJ.
For more information about the heat evolved, refer to the link:
https://brainly.com/question/24245395
How long will it take to do generate 70 watts of power if I do 4900 Jules of work? HELP ASAP WILL GOVE BRAINLIEST‼️‼️
Answer:
Is it multiple choice or what I need to know the details
Explanation:
find the volume of a gas at standard pressure if its volume at 1.9 atm is 80 ml?
given:
formula:
substitution:
answer:
Answer:
1.5 × 10² mL
Explanation:
Step 1: Given data
Initial pressure of the gas (P₁): 1.9 atmInitial volume of the gas (V₁): 80 mLFinal pressure of the gas (P₂): 1.0 atm (standard pressure)Final volume of the gas (V₂): ?Step 2: Calculate the final volume of the gas
For an ideal gas, we can calculate the final volume of the gas using Boyle's law.
P₁ × V₁ = P₂ × V₂
V₂ = P₁ × V₁/P₂
V₂ = 1.9 atm × 80 mL/1.0 atm
V₂ = 1.5 × 10² mL
Since the pressure decreased, the volume of the gas increased.
which two smaller groups is the animals kingdom is divided into
A. sponges and arthropods
B. vertebrates and invertebrates
C. ectotherms and endotherms
D. class and order
PLZZZZZZZZZZZ
NEED HELP ASAP!!!!!
Answer:
wersawess. uioiiiuioii
Explanation:
shhshsbshsjbsnsbxbxjzn, jznshdkbdjdjsnsj
Answer:
ok
asap what is the meaning of it?
Chlorine (Cl) is 76% chlorine-35 and 24% chlorine-37. Determine the average atomic mass of chlorine. Show/Explain work.
Answer:
Average atomic mass of chlorine is 35.48 amu.
Explanation:
Given data:
Percent abundance of Cl-35 = 76%
Percent abundance of Cl-37 = 24%
Average atomic mass = ?
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (76×35)+(24×37) /100
Average atomic mass = 2660 + 888 / 100
Average atomic mass = 3548/ 100
Average atomic mass = 35.48 amu
Average atomic mass of chlorine is 35.48 amu.
What masses of KCl and H2O are needed to make 250 g of 5.00 % solution?
____ g of KCl
____ g of H2O
Answer:
w/w means weight/weight
Therefore, in a 250 g of solution, 5% needs to be KCl,
i.e. 5% x 250 = 12.5 g of KCl is needed.
The masses of KCl and H2O are needed to make 250 g of 5.00 % solution is 12.5 g of KCl and 237.50 g of H2O.
Calculation of the masses:Since there is the solution of 250 g of 5.00 % solution
So, here
Mass of KCl is = 5% of 250 = 12.5 g
And, the mass of H2O is
= 250 - 12.5g
= 237.50 g
Hence, The masses of KCl and H2O are needed to make 250 g of 5.00 % solution is 12.5 g of KCl and 237.50 g of H2O.
Learn more about mass here: https://brainly.com/question/18470727.
Using the Rydberg equation, calculate the energy for the following electronic transitions in a hydrogen atom and label each as an absorption or an emission. When calculating, watch your signs!
n = 3 → n = 1
a. Energy calculation
b. absorption or emission?
Answer:
-1.94 * 10^-18 J
Since the electron moved from a higher to a lower energy level (n = 3 → n = 1) it is an emission.
Explanation:
From Rydberg equation;
E = -RH(1/n^2final - 1/n^2initial)
For a transition from n = 3 → n = 1
RH = 2.18 * 10^-18 J
E = -(2.18 * 10^-18) (1/1^2 - (1/3^2)
E = -(2.18 * 10^-18) (1-1/9)
E= -(2.18 * 10^-18) (8/9)
E = -1.94 * 10^-18 J
Omar heated a small piece of calcium carbonate. It gave off carbon dioxide gas, solid calcium oxide was left behind.write equation.
Answer:
CaCO[tex]_{3s}[/tex] → CO[tex]_{2g}[/tex] + CaO[tex]_{s}[/tex]
Explanation:
Given reactants:
Omar heated small piece of calcium carbonate
Product;
it gave off carbon dioxide gas and solid calcium oxide;
Problem,
Equation of the reaction;
Solution:
Calcium carbonate → Carbon dioxide + Calcium oxide
CaCO[tex]_{3s}[/tex] → CO[tex]_{2g}[/tex] + CaO[tex]_{s}[/tex]
an objects kinetic energy increases as its velocity increases?
Classify which compounds will dissolve in water and which ones will not dissolve in water.
a. Accetone
b. I-propanol
c. Hexane
d. Methanol
e. Decane
Answer:
Dissolves in water: Acetone, 1-propanol, Methanol
Do not dissolve in water: Hexane, Decane
Explanation:
From the principle that like dissolves like,polar substances will dissolve in polar solutions, while non-polar substances will dissolve in non-polar substances.
Water is a polar solution, therefore, polar substances will dissolve in it.From the given options:
Acetone is a polar molecule, therefore, it will dissolve in water.
1-propanol is a polar molecule, therefore, it will dissolve in water.
Hexane is a non-polar molecule, therefore, it will not dissolve in water.
Methanol is a polar molecule, therefore, it will dissolve in water.
Decane is a non-polar molecule, therefore, it will not dissolve in water
A ballon that contains 0.75 l of gad at 25 c is cooled to - 100 c. Calculate the new volume of the baloon
Answer:
0.44L
Explanation:
Given parameters:
Initial volume = 0.75L
Initial temperature = 25°C = 273 + 25 = 298K
Final temperature = -100°C = 273 + (-100) = 173K
Unknown:
New volume of the balloon = ?
Solution:
According to Charles's law;
"the volume of a fixed mass of a gas varies directly as its absolute temperature if the pressure is constant".
Mathematically;
[tex]\frac{V_{1} }{T_{1} }[/tex] = [tex]\frac{V_{2} }{T_{2} }[/tex]
V and T are temperature values
1 and 2 are the initial and final states
Insert the parameters and solve;
[tex]\frac{0.75}{298}[/tex] = [tex]\frac{V_{2} }{173}[/tex]
298V₂ = 129.75
V₂ = 0.44L
is trying to plate gold onto his silver ring. He constructs an electrolytic cell using his ring as one of the electrodes. He runs this cell for 94.6 minutes at 224.8 mA. How many moles of electrons were transferred in this process
Answer:
0.013 mole.
Explanation:
From the question given above, the following data were obtained:
Time (t) = 94.6 mins
Current (I) = 224.8 mA.
Mole of electrons (e) =?
Next, we shall convert 94.6 mins to seconds. This is illustrated below:
1 min = 60 s
Therefore,
94.6 mins = 94.6 min × 60 s / 1 min
94.6 mins = 5676 s
Thus, 94.6 mins is equivalent to 5676 s.
Next, we shall convert 224.8 mA to ampere (A). This can be obtained as follow:
1 mA = 1×10¯³ A
Therefore,
224.8 mA = 224.8 mA × 1×10¯³ A / 1 mA
224.8 mA = 0.2248 A
Thus, 224.8 mA is equivalent to 0.2248 A.
Next, we shall determine the quantity of electricity flowing in circuit. This can be obtained as follow:
Time (t) = 5676 s
Current (I) = 0.2248 A
Quantity of electricity (Q) =?
Q = it
Q = 0.2248 × 5676
Q = 1275.96 C
Finally, we shall determine the mole of electron by converting the quantity of electricity (i.e 1275.96 C) to number of electrons. This can be obtained as follow:
96500 C = 1 e
Therefore,
1275.96 C = 1275.96 C × 1 e / 96500 C
96500 C = 0.013 e
Thus, the mole of electron trasfered in the process is 0.013 mole.
Is freeze-drying a physical change or chemical change?
Answer:
Physical change because it can go back to its original form.
Explanation:
please help will give brainliest
Answer:
1st one is...
Explanation:
The 1st one is change in size or shape. 2nd one is formation of precipitate. 3rd one is physical change. 4th one is formation of gas.
How many molecules are in 650.0 g Mg(OH)₂ ?
Answer:
6.711 × 10²⁴ molecules Mg(OH)₂
General Formulas and Concepts:
Chemistry - Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:
Step 1: Define
650.0 g Mg(OH)₂
Step 2: Define conversions
Avogadro's Number
Molar Mass of Mg - 24.31 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of H - 1.01 g/mol
Molar Mass of Mg(OH)₂ - 24.31 + 2(16.00) + 2(1.01) = 58.33 g/mol
Step 3: Convert
[tex]650.0 \ g \ Mg(OH)_2(\frac{1 \ mol \ Mg(OH)_2}{58.33 \ g \ Mg(OH)_2} )(\frac{6.022 \cdot 10^{23} \ molecules \ Mg(OH)_2}{1 \ mol \ Mg(OH)_2} )[/tex]
= 6.71061 × 10²⁴ molecules Mg(OH)₂
Step 4: Check
We are given 4 sig figs. Follow sig fig rules.
6.71061 × 10²⁴ molecules Mg(OH)₂ ≈ 6.711 × 10²⁴ molecules Mg(OH)₂
Theodor Schwann was a German scientist who wanted to understand how different types of cells worked and performed functions in different tissues. He was one of the first to theorize that all living things are made up of cells.
Rudolf Virchow was a German doctor who wanted to discover the origin of diseases. He accepted the idea that all living things are made up of cells and extended the idea to theorize that many diseases are the result of bacterial cells infecting the body.
The example described above suggests that
A.
scientific discoveries are never made by doctors.
B.
scientists always have the same goals when making related discoveries.
C.
German scientists were the first to disprove cell theory.
D.
people with different goals can make contributions to scientific knowledge.
D. People with different goals can make contributions to scientific knowledge
Both Schwann and Virchow had different thoughts and ideas. Schwann wanted to understand how cells worked - Virchow wanted to know the origin of diseases. Different goals.
Answer:
D
Explanation:
I got it right on studyisland
