Answer:
A. color change
Explanation:
changing the color of a metal does not change its physical properties.
hope it helps.
For an investigation a student poured a blue solution of CuSO4 into a beaker. The student placed a shiny silver colored strip of zinc metal in the solution and observed the changes, The student inferred that a chemical reaction occurred. What evidence supports this inference?
Answer:
It is the second answer; A dark solid formed on the zinc.
Explanation:
This is the correct answer because when a solid is formed it is called a precipitate, which is commonly known as a chemical reaction.
The evidence that supports the student's inference is a dark solid formed on the zinc.
Chemical reaction of zinc metal with CuSO4When zinc is added to copper sulphate (CuSO4) solution, due to more reactivity of zinc, copper is replaced by zinc and forms zinc sulphate precipate.
Thus, the student is correct, there will be a chemical reatcion between the zinc and copper sulphate (CuSO4) solution, producing a dark solid substance.
Learn more about chemical reaction here: https://brainly.com/question/26018275
#SPJ2
How many moles of hydrogen atoms are there in 1.25 x 1025 molecules of ethane? (C2H6)
Answer:
124.56 moles of Hydrogen atoms.
Explanation:
We'll begin by calculating the number of moles of ethane that contains 1.25×10²⁵ molecules. This can be obtained as follow:
From Avogadro's hypothesis, 1 mole of any substance contains 6.02x10²³ molecules. This implies that 1 mole of ethane also contains 6.02x10²³ molecules.
Thus, 6.02x10²³ molecules are present in 1 mole of ethane.
Therefore, 1.25×10²⁵ molecules are present in = 1.25×10²⁵/6.02x10²³ = 20.76
Therefore, 20.76 moles of ethane contains 1.25×10²⁵ molecules.
Finally, we shall determine the number of mole of Hydrogen in 20.76 moles of ethane. This can be obtained as follow:
Ethane has formula as C2H6.
From the formula, 1 mole of ethane, C2H6 contains 6 moles of Hydrogen atoms.
Therefore, 20.76 moles of ethane will contain = 20.76 × 6 = 124.56 moles of Hydrogen atoms.
Therefore, 1.25×10²⁵ molecules of ethane contains 124.56 moles of Hydrogen atoms.
How many moles of methane (CH4) are there in 87.5g of methane (CH4)?
Which characteristic BEST identifies a pure substance?
a. shape
b. texture
c. melting point
d. state of matter
Whoever helps I will give BRAINLIEST
A
is an organism that eats other organisms to gain energy; it is also called
Answer:
A consumer
Explanation:
Organisms, such as plants, that produce their own food by methods such as photosynthesis are called producers.
Organisms that need to consume other organisms as their food source, including all animals, are consumers. Some consumers consume plants (primary consumers, or herbivores) but other consumers eat other consumers (secondary consumers, or carnivores)
Which will have both the highest ionization energy and the largest atomic
radius? Potassium, Bromine, Krypton
Answer:
Bromine
Explanation:
Cuz it has bro in it :)
Which of the following statements is true?
Erosion can be reduced by planting trees and other plants.
Warm air is more denser than cold air.
It forms areas of high pressure.
Most of the earth's freshwater is located deep below the crust.
The most abundance gas in the atmosphere is oxygen.
Answer:
erosion can be reduced by planting trees and other plants
Answer:
A
Explanation:
You are given a sample of a Group II metal chloride, but the identity of the metal is unknown. Knowing that all Group II metal chloride compounds have the general formula, MCI2 and that the percentage of chlorine in the compound is 34.1%, what is the identity of the unknown substance?
Answer:
The identity of unknown substance is Barium.
Explanation:
The given compound has a formula of MCl2. And the percentage of chlorine in this compound is said to be 34.1 %. But, we know that the mass of chlorine in this compound is, 35.5*2 = 71 g
Therefore, if we let x be the total mass of the compound, then:
34.1% of x = 71 g
(0.341)x = 71 g
x = 71 g/0.341
x = 208.2 g
Hence, the mass of other atom M, must be:
M = x - 71 g
M = 208.2 g - 71 g
M = 137.2 g
Now, we look into periodic table in group II. We find that the element is Barium with atomic mass of 137 g.
The identity of unknown substance is Barium.
Barium forms a metal chloride whose percentage of chlorine is 34.1 %. The unknown substance is barium chloride.
We have a Group II metal chloride with a general formula MCl₂. The molar mass of Cl⁻ is 35.45 g/mol. The mass of 2 moles of Cl⁻ is:
[tex]2 mol Cl^{-} \times \frac{35.45g Cl^{-} }{1mol Cl^{-} } = 70.90g Cl^{-}[/tex]
70.90 g represents 34.1% of 1 mole of MCl₂. The molar mass of MCl₂ is:
[tex]70.90gCl^{-} \times \frac{100gMgCl_2}{34.1gCl^{-} } = 208gMgCl_2[/tex]
208 g of MCl₂ contains 70.90 g of Cl⁻. The mass of M²⁺ in 1 mole of MCl₂ is:
[tex]mMCl_2 = mCl^{-} + mM^{2+} \\\\mM^{2+} = mMCl_2 - mCl^{-} = 208g-70.9 g = 137.1 g[/tex]
Barium has a molar mass of 137.3 g/mol, so M must be barium. The unknown substance is barium chloride.
Barium forms a metal chloride whose percentage of chlorine is 34.1 %. The unknown substance is barium chloride.
Learn more: https://brainly.com/question/5394922
ipt A wall that was once white is painted black. Which of the following is definitely true of the painted wall? A. Its chemical properties have changed. B. Its physical properties have changed. C. Both its physical properties and chemical properties have changed. D. None of its characteristic properties have changed.
Answer:
B It's physical properties changed
Explanation:
Because they painted the outside
3.7500*10^4+9.7100*5
Answer:
37548.55
Explanation:
3.7500*10^4+9.7100*5
3.7500*10000+9.7100*5
37500+48.55
37548.55
Which has the lowest pH?
water
baking soda
bleach vinegar
Answer:
c. baking soda
Explanation:
Cl2 is a stable diatomic molecule. It can be decomposed to form two Cl atoms as
shown below.
Cl2 → 2Cl(9)
Predict the change in enthalpy (AH) of this reaction.
A) AH is (-); endothermic
B) AH is (+); endothermic
C) AH is (-); exothermic
D) AH is (+); exothermic
E) AH = 0; thermoneutral
Answer:
Option B: ΔH is (+); endothermic
Explanation:
From the reaction Cl2 → 2Cl(g) given, we can see that the number of moles on the left hand side is 1 while on right hand side, it is 2. This means the number of moles are increasing and it means that the randomness of the system has increased. Also, the bonds are being broken down.
Therefore, the reaction is endothermic. In endothermic reactions, ΔH is positive.
Thus, the correct option is option B.
Answer:
b
Explanation:
ah
What is the relationship between density and viscosity?
Answer:There is no relationship between the viscosity and density of a fluid. While viscosity is the thickness or thinness of a fluid, density refers to the space between its particles. However, both properties are affected by temperature. When a fluid is heated, its particles move far apart, and it also becomes less viscous.
3. Which of the following is the correct notation for an isotope with 3 protons and 5 neutrons?
A. 5/3Li
B. 3/5B
C. 8/3 Li
D. 8/5 B
Answer:
option c
Explanation:
neutros equal to mass num - atomic num
An atom can be defined by its properties:
Atomic number (Z): It is equal to the number of protons present in a neutral atom.Mass number (A): It is equal to the sum of the number of protons and the number of neutrons.An isotope is represented by the general notation of [tex]_Z^A\textrm{Y}[/tex], where X is the symbol of an element.
Mass number = Numer of protons + Number of neutrons
Put the value in the above formula.
[tex]\Rightarrow \text{Mass number}=3+5[/tex]
[tex]\Rightarrow \text{Mass number}=8[/tex]
The isotopic representation of the chemical specie is [tex]_3^8\textrm{Li}[/tex]. So, the correct option is C.
Learn more about isotopic representation: https://brainly.com/question/18210355
Fluorine has seven electrons in its outermost shell. It will most likely try to join with an atom with _____.
seven electrons in its outermost shell
two electrons in its outermost shell
one electron in its outermost shell
eight electrons in its first shell
Answer:
Its either with itself to become fluoride Fl2 or with an alkali metal (elements in group 1) to achieve a stable electronic configuration or octet structure
Explanation:
The skeletal structure in line-angle (line-bond) mode of 2,3,3,5-tetramethylhexane is shown. Identify the number of hydrogen atoms bound to each carbon atom in the structure.
Answer:
There are 22 hydrogen in 2,3,3,5-tetramethylhexane (C10H22)
From the left to the right of the skeletal structure:
1st Main Carbon = 3 hydrogen
2nd Main Carbon = 1 hydrogen
1st Branch Carbon = 3 hydrogen
3rd Main Carbon = 2 hydrogen
2nd Branch Carbon = 3 hydrogen
3rd Branch Carbon = 3 hydrogen
4th Main Carbon = 0 hydrogen
4th Branch Carbon = 3 hydrogen
5th Main Carbon = 1 hydrogen
6th Main Carbon = 3 hydrogen
Total = 22 hydrogen
Explanation:
This is the skeletal formula for 2,3,3,5-tetramethylhexane - the 2D chemical structure. It is an organic compound. The carbon atoms in the structure are known as the carbon backbone. The hydrogen atoms are linked to the carbon backbone. This provides each carbon atom with four bonds.
What does Prokaryotic have that other cells does not
Answer:
Prokaryotes are unicellular organisms that lack membrane-bound structures, the most noteworthy of which is the nucleus. ... While prokaryotic cells do not have membrane-bound structures, they do have distinct cellular regions. In prokaryotic cells, DNA bundles together in a region called the nucleoid.
Why don't solids, liquids, and gases leave Earth's atmosphere? A) Only gases can leave the atmosphere. B) Matter on Earth is destroyed and recycled. C) Gravity keeps all matter on Earth.
Answer:
The answer is C) Gravity keeps all matter on Earth.
Explanation:
I took the test and this was correct!
(Not a fake answer like some, I promise!)
Which of the following shows the abbreviation for an Sl unit of density?
A. L/kg
B. g/mL
C.
g/cm
D. kg/m2
Explanation:
ur answer okkkkkkkkkkkkkkkkll
What is the chemical name for LiC2H3O2 or C2H3O2Li
Answer:
AWAWDWDAD
Explanation:
can you guys match the words to the definitions for my science work on thermal energy please❤️?
Answer:
i dont feel like typin the whole definition so im jus gonna type the number with the word
1- temperature
2- laws of conservation of energy
3- boiling point
4- freezing point
5- joule
6- thermal energy
7- heat
8- solid
9- liquid
10- gas
Answer:
hey guys
Explanation:
hope this helps you to do something good
Solve. C3H8(g) + 5O2(g) --> 3CO2(g) + 4H2O(g)
What is the Enthalpy of reaction?
What is the total Enthalpy of Reactants and Products? (Kj/Mol)
Is this a endothermic or exothermic reaction?
Answer: hope this helps!
Explanation:
Specific heat capacity of a substance is the amount of heat required to raise the temperature by one degree Celsius of one gram of a substance. Therefore, the enthalpy of reaction is -2219.9KJ/mol and the reaction is exothermic reaction.
What is Enthalpy?Enthalpy term is basically used in thermodynamics to show the overall energy that a matter have. Mathematically, Enthalpy is directly proportional to specific heat capacity of a substances.
Mathematically,
C[tex]_3[/tex]H[tex]_8[/tex](g) + 5O[tex]_2[/tex](g) [tex]\rightarrow[/tex]3CO[tex]_2[/tex](g) + 4H[tex]_2[/tex]O(g)
Mathematically, the formula for enthalpy of a reaction can be given as
ΔH for reaction= 3 ×ΔH of CO[tex]_2[/tex] + 4 ×ΔH of H[tex]_2[/tex]O- ΔH of C[tex]_3[/tex]H[tex]_8[/tex]+ 5 ×ΔH of O[tex]_2[/tex]
= 3 ×393.5KJ/mol+ 4 ×285.8- 103.8+ 5 ×0
=-2219.9KJ/mol
The enthalpy of reaction is -2219.9KJ/mol. since the value of enthalpy has negative sign, the reaction is exothermic reaction.
Therefore, the enthalpy of reaction is -2219.9KJ/mol and the reaction is exothermic reaction.
To know more about enthalpy, here:
https://brainly.com/question/24170335
#SPJ2
What is the name of the molecular geometry (shape) for this Lewis structure?
Answer:
Trigonal Pyramidal
Explanation:
You have [tex]AX_3E_1[/tex] configuration which corresponds to a trigonal pyramidal structure.
50 POINTS PLEASE HELP!!
What was the volume of air that has a volume of 6.00L at 120870 Pa, if the original pressure was 250020 Pa?
Answer:
120876
Explanation:
pls answer and i will mark u brainliest
question:- A precious metal used in jewelry and found in a pure form in nature is:
options are :-
a. Silver
b. platinum
c. Zinc
d. copper
Calculate the mass of aluminum that would have the same number of atoms as 6.35 g of cadmium
Answer:
1.62 g of Al contain the same number of atoms as 6.35 g of cadmium have.
Explanation:
Given data:
mass of cadmium = 6.35 g
Number of atoms of aluminum as 6.35 g cadmium contain = ?
Solution:
Number of moles of cadmium = 6.35 g/ 112.4 g/mol
Number of moles of cadmium = 0.06 mol
Number of atoms of cadmium:
1 mole = 6.022×10²³ atoms of cadmium
0.06 mol × 6.022×10²³ atoms of cadmium/ 1mol
0.36×10²³ atoms of cadmium
Number of atoms of Al:
Number of atoms of Al = 0.36×10²³ atoms
1 mole = 6.022×10²³ atoms
0.36×10²³ atoms × 1 mol /6.022×10²³ atoms
0.06 moles
Mass of aluminum:
Number of moles = mass/molar mass
0.06 mol = m/ 27 g/mol
m = 0.06 mol ×27 g/mol
m = 1.62 g
Thus, 1.62 g of Al contain the same number of atoms as 6.35 g of cadmium have.
What happens during a chemical reaction? Where do the reactants go, and where do the products come from?
The two most common isotopes of argon (Ar) are argon-36 and argon-40. Given that the average atomic mass is 39.95, what can be said about the relative abundance of each isotope? Which is more common and how do you know? No calculation is necessary. I am looking for a simple written response.
Answer:
Argon-40
the reason this is abundent is because this is a more common isotope
Explanation:
Of the atoms below, __________ is the most electronegative.
PLZ HELP I'LL AWARD BRINLIEST.
Hello sir, The answer that you are looking for is fluorine. Fluorine is the most electronegative atom. I am also sorry for calling you sir. I didn't know you were a woman.
PLZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
Answer: I think G.
Explanation:
Answer:
I believe its student 2 as well. it's most definitely g