Answer:
To remove impurities
Explanation:
Impurities may react with other chemicals if you are still continuing with the experiment.
Multiple choice
I genuinely have no idea-- but I don't think it's the first one or the last.
I think it may be the third one but I'm not too sure.
Answer:
The correct option is;
By first reversing Reaction 2 and then adding the enthalpy of Reaction 1 and the enthalpy of reaction 2
Explanation:
The given reactions are;
1) C₂H₂ (g) + 2H₂ (g) → C₂H₆ (g) [tex]{}[/tex] ΔH = -75 kcal
2) C₂H₄ (g) + H₂ (g) → C₂H₆ (g) [tex]{}[/tex] ΔH = -33 kcal
3) C₂H₂ (g) + H₂ (g) → C₂H₄ (g) [tex]{}[/tex] ΔH = ?
By reversing reaction (2) and subtracting the reactants from the products we then have followed by adding the enthalpy of reaction 1 to the value of the enthalpy of the (reversed) reaction 2, we have;
C₂H₂ (g) + 2H₂ (g) → C₂H₆ (g) [tex]{}[/tex] ΔH = -75 kcal
C₂H₆ (g) → C₂H₄ (g) + H₂ (g) [tex]{}[/tex] ΔH = 33kcal
Adding, and cancelling out the italicized terms which are repeated in the product and reactants, we get
C₂H₂ (g) + H₂ (g) → C₂H₄ (g) [tex]{}[/tex] ΔH = -75 kcal + 33 kcal = -42 kcal
Therefore, the correct option is "by first reversing Reaction 2 and then adding the enthalpy of Reaction 1 and the enthalpy of reaction 2"
what are the 10 properties of metals
Explanation:
Lustrous (shiny)
Good conductors of heat and electricity.
High melting point.
High density (heavy for their size)
Malleable (can be hammered)
Ductile (can be drawn into wires)
Usually solid at room temperature (an exception is mercury)
Opaque as a thin sheet (can't see through metals)
which is NOT represented in a chemical change demonstrated chemical reactions?
Answer:
Option C
Explanation:
A) A chemical equation is simply the symbolic representation of a chemical reaction using the form of symbols and formulae. Thus, option A is not the answer.
B) A product is the substance that shows at the end of a chemical reaction. Thus, option B is not the answer.
C) Law of conservation of mass in chemistry states that even in chemical reactions or physical transformations, that mass cannot be created nor destroyed. Which means that mass is conserved. This has nothing to do with chemical change demonstrated chemical reactions. Thus, option C is correct.
D) reaction rate is the speed that a chemical reaction occurs. Thus, options D is not correct.
Examine the molecules. H2O HCl HF What do all three molecules have in common?
All of the molecules are nonpolar compounds.
All of the molecules contain an alkaline earth metal.
All of the molecules are polar covalent compounds.
All of the molecules are diatomic.
Answer:
polar
Explanation:
because interaction between them is hydrogen bonds
Si dos elementos tienen igual valor del número cuántico n y diferente l, ml y ms entonces deben estar en : El mismo orbital, pero diferente nivel y sub nivel. Diferente nivel , subnivel y orbital El mismo nivel, sub nivel y orbital. El mismo nivel, pero diferente subnivel y orbital El mismo sub nivel y orbital pero diferente nivel.
Answer:
El mismo nivel, pero diferente subnivel y orbital
Explanation:
En un átomo, el número cuántico principal n muestra el nivel de energía del electrón.
Si dos electrones tienen el mismo valor del número cuántico principal n, simplemente significa que están en el mismo nivel de energía.
Sin embargo, cuando los números cuánticos l y ml difieren, los electrones deben estar en diferentes subniveles y orbitales.
What is the likely origin of the two moons orbiting Mars?
Answer:
....? What-
Explanation:
What is the ionic formula of the compound formed by Co3+ and the phosphorus ion? What is the name of the compound formed based on the ionic compound formula?
Answer: The ionic formula of compound is [tex]CoP[/tex] and the name is cobalt phosphide.
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here element Co is having an oxidation state of +3 called as [tex]Co^{3+}[/tex] cation and phosphprous forms [tex]P^{3-}[/tex] anion with oxidation state of -3. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral [tex]CoP[/tex]
The nomenclature of ionic compounds is given by:
1. Positive is written first followed by the oxidation state of metal in roman numerals in square brackets.
2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.
Thus the name of [tex]CoP[/tex] is cobalt phosphide.
Answer: A
Explanation: TOOK THE QUIZ !)) 200 YEARS AGOO
The outer energy level of a noble gas is
Select one:
a. empty.
b. filled.
c. half-filled.
PLEASE HELP ME DUDE MY CLASS ENDS IN LIKE HALF A DAY
Answer:
c.all atoms have the same arrangement for electrons
Answer:
C because the number of protons and neutrons add up to make the number of electrons.
10 points
3. Which of the following is the characteristic that all organisms have in
common?*
O A. All organisms are made up of cells.
O B. All organisms are multicellular.
C. All organisms can make their own food.
O D. All organisms have cells with a nucleus.
Answer:
A all organisms are made of 1 or more cells
how many moles do you have in 37.3 g of Co(CrO4)3
Answer:
0.0917 mol Co(CrO₄)₃
General Formulas and Concepts:
Chemistry - Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisExplanation:
Step 1: Define
37.3 g Co(CrO₄)₃
Step 2: Identify Conversions
Molar Mass of Co - 58.93 g/mol
Molar Mass of Cr - 52.00 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of Co(CrO₄)₃ - 58.93 + 3(52.00) + 12(16.00) = 406.93 g/mol
Step 3: Convert
[tex]37.3 \ g \ Co(CrO_4)_3(\frac{1 \ mol \ Co(CrO_4)_3}{406.93 \ g \ Co(CrO_4)_3} )[/tex] = 0.091662 mol Co(CrO₄)₃
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
0.091662 mol Co(CrO₄)₃ ≈ 0.0917 mol Co(CrO₄)₃
URGENT !! PLEASE ANSWER !!
Is H-F a nonpolar or polar covalent bond? why?
Answer:
It's polar
Explanation:
Hydrogen has an EN of 2.1 and Fluorine an EN of 4.0 (highest EN of any element). So do: 4.0−2.1=1.9.
Which of the following elements has the highest electronegativity?
O A. Rubidium (RD)
B. Calcium (Ca)
C. Silicon (Si)
O D. Nitrogen (N)
Answer:
I got fluorine for my guess
Explanation:
Answer:
It's D Nitrogen with 3.04
1)how many red blood cells could you line up across the grain of sand?
2) How many red blood cells could you line up across the diameter of a penny (0.02 m)?
Please I need helpppppp
Answer:
The correct answer is -
1. 1 grain of sand = 244 red blood cells.
2. 1 penny = 2439
Explanation:
A normal red blood cell has a normal disk diameter of 6.2 - 8.2 micron or micrometer is way small than a grain of sand which ranges in diameter from 0.0625 mm (or 1⁄16 mm) to 2 mm. The size of the diameter of a penny is given 0.02 m.
Let take the highest value of them:
RBC = 8.2 micrometer
The grain of sand = 2 mm
Penny = 0.02 m
we know:
1 meter = 10e+6 or 100000 micron
1 millimeter = 1000 micron
then, the grain of sand = 2* 1000 = 2000
so, the 1 grain sand = 2000/8.2
= 244
Similarly,
Penny = 0.02*100000= 20000
= 2439
Thus, the correct answer is =
1. 1 grain of sand = 244 red blood cells.
2. 1 penny = 2439
Predict the products of the following reaction: Zn(ClO₃)₂ (aq) + K₃PO₄ (aq)
The products : Zn₃(PO₄)₂ (s) + KClO₃ (aq)
Further explanationGiven
reaction: Zn(ClO₃)₂ (aq) + K₃PO₄ (aq)
Required
The products
Solution
Double-Replacement reactions : an ion exchange between two ion compounds in the reactant to form two new ion compounds in the product
General formula :
AB + CD ⇒ AD + CB
One of the characteristics of the double replacement reaction is the presence of precipitated compounds
Zn(ClO₃)₂ (aq) + K₃PO₄ (aq) ⇒ Zn₃(PO₄)₂ (s) + KClO₃ (aq)
Zn₃(PO₄)₂ (s)⇒ precipitated compounds, so that this reaction can occur
Which of the following is an example of a physical change?
A) pouring hydrogen peroxide (H202) on a cut, causing oxygen (02) bubbles to form
B) mixing together flour, sugar, salt, eggs and butter to make cookies
c) baking a birthday for your best friend
D) enzymes within the digestive system breaking down the lunch you just ate
Answer:
B! i just learned this last week lol!
Explanation:
hope this helps♡♡
how many moles are in 100.0 g of gold?
Answer:
196.96655
Explanation:
The answer is 196.96655. I assume you are converting between grams Gold and mole. The molecular formula for Gold is Au. The SI base unit for the amount of substance is the mole.
The quantity present in an atom or molecules of a given substance is called moles it is written as mol and is calculated with the help of molar mass and mass of the given substance.
0.507699 mol is present in the 100 gm of gold.
Moles of gold can be calculated by:Given,
Mass (m) = 100 gmThe atomic weight of Au (M) = 196.967The formula for calculating moles is:
[tex]\rm Moles (n) = \dfrac{Mass}{Molar \;mass}[/tex]
Substituting values in the formula:
[tex]\begin{aligned}\rm n & = \dfrac{100}{196.967}\\\\ & = 0.507699 \;\rm mol\\\\& = 0.5077\;\rm mol\end{aligned}[/tex]
Therefore, 0.5077 mol is present in 100 gm of gold.
Learn more about moles here:
https://brainly.com/question/6260819
Your weight changes if you travel to the moon because _____.
Answer:
1/6 of your weight on Earth
Answer:
the amount of the force of gravity changes
calculate the total bond energy for a water molecule using the bond energy chart provided.
Answer:
21 periodic tables equals alot of stuff
Explanation:
A soft weak like layer the upper part of the mantle where lithosperic plates and more
Answer:
asthenosphere
Explanation:
What is being described in the question above, that is a soft weak like layer the upper part of the mantle where lithospheric plates is known as the asthenosphere. In the study of earth's mantle, the asthenosphere is one of the region that can be overlooked as it constitutes part of the upper mantle with its counterpart; lithosphere.
Some of the properties of asthenosphere is the fact it has high temperature, it is viscous and it is ductile. It is also characterized by its density.
0.12g of rock salt was dissolved in water and titrated with 0.1moldm^-3 silver nitrate until the first permanent brown precipitate of silver chromate is seen. 19.70 cm^3 was required to titrate all the chloride ion. how many moles of chloride ion were titrated? what mass of sodium chloride was titrated? what was the % purity of the rock salt in terms of sodium chloride?
moles Cl⁻ : 0.00197
mass NaCl : 0.115
% purity : 95.83%
Further explanationMolarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution
[tex]\large \boxed {\bold {M ~ = ~ \dfrac {n} {V}}}[/tex]
Where
M = Molarity
n = Number of moles of solute
V = Volume of solution
So to find the number of moles can be expressed as
n = V x M
mol Cl⁻Reaction
AgNO₃ + NaCl ⇒ AgCl + NaNO₃
Molarity(concentration) of AgNO₃ = 0.1 mol/dm³(L) = 0.1 M
Volume=V of AgNO₃ = 19.7 ml(cm³)
so mol of AgNO₃ :
[tex]\tt mol=M\times V\\\\mol=0.1~mol/L\times 0.0197~L\\\\mol=0.00197[/tex].
From the equation, mol ratio AgNO₃ : NaCl = 1 ; 1, so mol NaCl= mol AgNO₃= 0.00197
NaCl⇒Na⁺+Cl⁻
mol Cl⁻ : mol NaCl = 1 : 1, mol Cl⁻ = 0.00197
mass NaCl (MW=58.5 g/mol) :
[tex]\tt mass=mol\times MW\\\\mass= 0.00197\times 58.5=0.115~g[/tex]
% purity :[tex]\tt \%purity=\dfrac{mass~NaCl}{mass~rock}\times 100\%\\\\\%purity=\dfrac{0.115}{0.12}\times 100\%=95.83\%[/tex]
can someone help me please
Answer:
From left box to right box: Footwall, fault plane, hanging wall
Explanation:
A foot wall is the one holding us the hanging wall so the highest piece. Think of rock climbing. You put your feet on the wall or rocks to push yourself up. The foot wall is the rocks for the hanging wall.
The hanging wall is the part that's "hanging" from the other wall. So the lowest one. Think of it as the part that's hanging.
A fault plane is where the place where the fault happens which would be where there is the difference in elevations originate from. Think of it like the crack in the middle.
Don't be afraid to reach out if you need further help, I hope this helps!
Help needed ASAP
= Select all that apply
Natural selection _____.
[] is random
[] cannot work if beneficial traits are not hereditary
[] is often called survival of the fittest
[] favors organism well adapted to the environment
Natural selection cannot work if beneficial traits are not hereditary
Answer:
favors organisms well adapted to the environment
cannot work if beneficial traits are not hereditary
is often called survival of the fittest
Explanation:
NOT
is random
happens by chance
Which of the following options correctly ranks solid iodine, liquid bromine, and chlorine gas in order of increasing intermolecular force strength?
A solid iodine
B. solid iodine < chlorine gas
C. chlorine gas
o
D. liquid bromine < solid iodine
Answer:
solid iodine chlorine gas
The correct order for ranking solid iodine, liquid bromine, and chlorine gas in order of increasing intermolecular force strength is; chlorine gas < liquid bromine < solid iodine.
Intermolecular forces are forces that hold substances together in a particular state of matter. Intermolecular forces increase in the order; gases < liquids < solids. Solids have the highest magnitude of intermolecular interaction between particles.
Bearing this in mind, the correct order for ranking solid iodine, liquid bromine, and chlorine gas in order of increasing intermolecular force strength is; chlorine gas < liquid bromine < solid iodine.
Learn more: https://brainly.com/question/9328418
(HELP PLEASE )A solid is being cooled down.
What is happening to the particles of the solid?
Answer: the vibration becomes faster
Explanation:
All matter is involved in motion of some kind. True or false
Answer:
true
Explanation: all matter down to the molecular or even atomic level has a constant vibration and movement. The only time that any matter could stop moving would be at absolute zero.
Explain the van der Waal's
pressure and volume correction in an ideal gas equation
Answer:
The pressure correction in the ideal gas equation accounts for the intermolecular attractive forces between gas molecules. Vanderwaal constant 'a' measures the magnitude of intermolecular attractive forces between the particles.
Thevolume correction to the total volume per mole occupied by gas molecules, it closely corresponds to the volume per mole of the liquid state, whose molecules are closely layered. Vanderwaal constant 'b' measures the volume excluded by a mole of particles.
Vander waals equation followed by real gas is:
[tex](P+\frac{an^2}{V^2})(V-nb)=nRT[/tex]
where,
P = pressure of gas
V = volume of gas
n = number of moles of gas
R = gas constant
T = temperature of gas
1 mole is = how many grams of copper?
Answer:
63.55 g
Explanation:
The relation between molecular (formula) mass and molar mass Page 4 4 • To obtain one mole of copper atoms (6.02 x 1023 atoms), weigh out 63.55 g copper. The molar mass (M) of a substance is the mass of one mole of entities (atoms, molecules, or formula units) of the substance.
Answer:
63.55 Grams.
Explanation:
Give an example of a diatomic molecule found in Earth's atmosphere.
Answer:
oxygen is an example of a diatomic molecule found in earth's atmosphere!
Explanation:
A particle with no charge is a_____?
Answer:
a particle with no charge is a neutron.