Answer:
[tex]\boxed {\boxed {\sf A. \ Change \ in \ state \ of \ matter}}[/tex]
Explanation:
A physical change occurs when only the physical properties change. They are generally reversible and no new substances are formed.
However, in a chemical change, the chemical structures and properties change, plus new substances are formed.
Let's analyze each answer choice.
1. Change in state of matter
The state of matter is a physical property, so this is a physical change.
2. Precipitate was formed
A precipitate is a solid formed in a liquid solution. This is a new substance and a chemical change.
3. Unexpected change in odor.
A change in odor is a sign of chemical change.
4. Formation of bubbles
Bubbles signify the formation of gas or a new substance.
So, the best answer choice is A. change in state of matter
Question:
Which of the following would be the evidence of a physical change?
a. change in state of matter
b. precipitate was formed
c. unexpected change in odor
d. formation of bubbles
Answer:
A. Change in state of matter!
Explanation:
How to know it evidence of physical change!
EXPECTED color change.Change in SIZE or SHAPE.Change in state of matter.Reversible.No NEW substance formed!the law of conversation of mass states that the mass of the reactant is ___ the mass of products
Answer: equal to
Explanation:
describe a difference in our inner planets and outer planets
What volume, in liters, does 128 grams of O2 occupy at STP?
89.6 L
22.4 L
67.2 L
44.8 L
Answer: 89.7 L
Explanation:
89.6 volume, in liters, does 128 grams of O2 occupy at STP. Therefore, option A is correct.
What do you mean by volume ?A volume is simply the amount of space taken up by any three-dimensional solid. A cube, a cuboid, a cone, a cylinder, or a sphere are examples of solids. Volumes differ depending on the shape.
Every three-dimensional object requires some amount of space. The volume of this space is measured. Volume is defined as the space occupied by an object within the boundaries of three-dimensional space. It is also known as the object's capacity.
1 mole Oxygen has mass 32 grams
Mole of Oxygen in 128 g mass = 128 g / 32 g/mol
= 4.0 mol O2
At Standard temperature and pressure this has volume
= 4.0 mol × 22.4 L/mol
= 89.6 L
Thus, 89.6 volume, in liters, does 128 grams of O2 occupy at STP, option A is correct.
To learn more about the volume, follow the link;
https://brainly.com/question/1578538
#SPJ6
The parts of the Earth that contain living organisms
Answer:
Biosphere
The Biosphere --contains all the planet's living things. This sphere includes all of the microorganisms, plants, and animals of Earth. Within the biosphere, living things form ecological communities based on the physical surroundings of an area.
Explanation:
Answer:
Biosphere
Explanation:The Biosphere --contains all the planet's living things. This sphere includes all of the microorganisms, plants, and animals of Earth. Within the biosphere, living things form ecological communities based on the physical surroundings of an area. hope this helps (:
1) how can you make a solution more concentrated
Explanation:
solvent bc when you remove it it becomes more concentrate
An effective treatment for some cancerous tumors involves irradiation with "fast" neutrons. The neutrons from one treatment source have an average velocity of 3.5×107 m/s. If the velocities of individual neutrons are known to within 2.0% of this value, what is the uncertainty in the position of one of them?
Answer:
4.54 * 10^-14 m
Explanation:
From Heisenberg's uncertainty principle, we can write;
Δp.Δx ≥ h/4π
Given that;
Δp =Δmv
So;
Δmv.Δx ≥h/4π
Δmv =2/100(3.5×10^7 m/s * 1.66 * 10^-27)
Δmv =1.162 * 10^-21 Kgms-1
Δx ≥6.63 * 10^-34 /4 * 3.142 * 1.162 * 10^-21
Δx ≥4.54 * 10^-14 m
Which of the following has the smallest atomic radius?
a B
b Al
c F
d N
e Ga
Answer:
c. F
Explanation:
As you go top to bottom down a column of the periodic table, atomic radius increases.
As you go left to right across a period of the periodic table, atomic radius decreases.
Knowing this trend, that means that the smallest atomic radius would be located in the top right of the periodic table. The closest element to that point is fluorine, or answer C.
How many moles is 118 grams of Argon
Answer:
[tex]\boxed {\boxed {\sf About \ 2.96 \ moles \ of \ Argon}}[/tex]
Explanation:
To convert from grams to moles we must use the molar mass, which is found on the Periodic Table.
Argon: 39.9 g/molUse the molar mass as a ratio.
[tex]\frac{39.9 \ g \ Ar}{1 \ mol \ Ar}[/tex]
Multiply by the given number of grams: 118
[tex]118 \ g \ Ar *\frac{39.9 \ g \ Ar}{1 \ mol \ Ar}[/tex]
Flip the fraction so the grams of argon will cancel each other out.
[tex]118 \ g\ Ar * \frac{1 \ mol \ Ar}{39.9 \ g \ Ar}[/tex]
[tex]118 * \frac{ 1 \ mol \ Ar}{39.9 \ g \ Ar}[/tex]
[tex]\frac {118 \ mol \ Ar }{ 39.9 }[/tex]
[tex]2.95739348 \ mol \ Ar[/tex]
The original measurement of grams had 3 significant figures, so our answer must have 3 sig figs.
For the number we calculated, that is the hundredth place. The 7 in the thousandth place tells us to round the 5 to a 6.
[tex]2.96 \ mol \ Ar[/tex]
There are about 2.96 moles of Argon in 118 grams.
A screw decreases the amount of work done.
True
False
Answer:
tru
Explanation:
Draw a model to represent the physical property of metals known as ductility, or the ability to be drawn into a wire.
The model that represents the physical property of metals known as ductility can be seen in the image attached below.
Metals are substances that are good conductors of heat and electricity.
The term ductility is a characteristic of metal and it explains the ability of metals to be drawn into wire. it implies that metal materials can be hammered and beaten into tiny sheets of wires.
The model in the image attached below shows how gold which is metal is drawn into wires.
Learn more about metals here:
https://brainly.com/question/25090336?referrer=searchResults
who is princess tianas best friend, if you can get her name right then ill give you brainliest
Answer:
Oo i think her name is Tiana..... ❤️❤️Answer:
Charlotte La Bouff
Explanation:
"Lottie" if you will
How does Natural selection lead to the Evolution of bacteria?
Answer:
Bacteria can evolve quickly because they reproduce at a fast rate.
Explanation:
Bacteria can evolve quickly because they reproduce at a fast rate. Mutations in the DNA of bacteria can produce new characteristics. A random mutation might cause some bacteria to become resistant to certain antibiotics, such as penicillin.
The useful energy a light bulb gives out is
(a). kinetic energy (b) chemical energy (c) light energy
science subject
Answer:
Light bulb gives light energy which is usefull
Answer:
(c) light energy
Explanation:
As bulb is used for giving light and hence the energy that it gives is light energy.
How many moles of water are produced from the reaction of oxygen with four moles of propane (C3H8)? C3H8 + 5O2 --> 3CO2 + 4H2O
Answer:
Explanation:
The reaction is:
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
We see, that the equation is ballanced.
As we have data from only one reactant, we assume the other is in excess.
Ratio is 1:4 (stoichiometry). We solve this, by a rule of three:
1 mol of propane can produce 4 moles of water
Then, 4 moles of propane, may produce
( 4 . 4 ) /1 = 16 moles of water can be made.
Remember, we always have to work with the limiting reactant.
A mixture of metals with properties different than the metals by themselves is called a(n) __________.
Answer:
Alloy
Explanation:
if I have a +2 oxidation number do I give up or accept electrons?
Answer:
I will give up the electrons
Explanation:
Consider the following rules:
1. An atom loses electrons if its oxidation number is positive.
2. An atom gains electrons if its oxidation number is negative.
3. An atom neither gains nor loses electrons if its atomic number is zero.
As I have an oxidation number [tex]+2[/tex] that is oxidation number is positive, so, I will give up electrons.
What is the answer, just the letter. No explanation needed
Answer:
Explanation:
f i did this in my class
Answer:
3 rd
Explanation:
yes answer is 3 you can go with it
Use the periodic table to determine which of the
following could be an isotope of bromine (Br).
Check all that apply.
Z = 79, A = 196
Z = 35, A = 79
A = 79, N =44
D Z = 44, N = 44
DONE
I NEED HELP ASAP PLS
picture included^^^^^^ ^^
brainliest;) ^
Explanation:
20g of Na and 10g of Cl2 which is in excess?
The equation of the reaction is given as;
2 Na + Cl2 --> 2 NaCl
From the equation;
2 mol of Na reacts with 1 mol of Cl2
Converting the masses of reactants given to mol
Number of moles = Mass / Molar mass
Na;
Number of moles = 20 / 23 = 0.8696 mol
Cl2;
Number of moles = 10 / 71 = 0.1408 mol
In the chemical equation, the ratio was 2: 1 however with the masses, we can tell that Na is in by far excess.
0.8696 mol of Na would require 0.4348 of Cl2 (Present = 0.1408 mol)
This means;
Na - Excess Reactant
Cl2 - Limiting Reactant
Second part; How much NaCl would be produced?
The limiting reactant determines how much of the product is formed.
From the equation of the reactant;
1 mol of Cl2 produces 2 mol of NaCl
0.1408 mol of Cl2 would require x mol of NaCl
1 = 2
0.1408 = x
x = 0.2816 mol of NaCl
Converting to mass;
Mass = Molar Mass * Number of moles
Mass = 58.44 g/mol * 0.2816 mol
Mass = 16.46 g
the substance that can not be further decomposed by ordinary chemical means is
A.water
B.gold
C.sugar
D.air
how many valence electrons does hydrogen have
Answer:
Since hydrogen is the first element, its electron configuration is 1s1.
Explanation:
It has only one electron in its valence shell.
Valence electrons are the outermost electrons or electrons in the largest energy level. Hydrogen has only one electron, so that electron is a valence electron.
Answer:
One valence electron !!
Explanation:
which one of these is NOT a unit for a reaction rate. 1) g/mL 2) M/min
how many grams of H2O are in 3.00 moles of H2O?
Answer:
mole=mass/molarmass
Explanation:
molar mass of h2o=18
What are land plants used for?
Answer:
Land plants are also known as Embryophytes. Embryophytes are complex multicellular eukaryotes with specialized reproductive organs. The name derives from their innovative characteristic of nurturing the young embryo sporophyte during the early stages of its multicellular development within the tissues of the parent gametophyte.
Explanation:
Answer:
there used for mountains , wait I'm just trynna get points ya feel me
Explanation:
AgNO3 ionic or covalent
Answer:
what i need more details
Explanation:
Answer:
Ionic
Explanation:
AgNO3 is also highly soluble in water. Ionic means that the compound is composed of ions.
Which type of fertilization is common with animals that live in the water?
1. external fertilization
2. sexual
3. internal fertilization
4. asexual
External fertilization in animals usually occurs in water or in damp areas in a process called spawning.
16. Keesha performed a chemical reaction, and the products looked quite
different from the reactants. She knew the amount of matter had not
changed due to the law of conservation of mass. According to the law of
conservation of mass, what happens in a chemical reaction? *
Answer:
it's the third one
Explanation:
matter can't change, but mass can differ
energy traveling as electromagnetic waves
Radiant
Thermal
Chemical
Mechanical
How many electrons are being shared between the two carbon atoms in the covalent compound ethyne? Ethyne has the structure: H−C≡C−H
Answer:
Three lines between the carbon atoms in the Lewis structure represent three covalent bonds. Each covalent bond is a shared pair of electrons, hence there are six electrons being shared between the carbon atoms in ethyne.
The number of electrons that are being shared between the two carbon atoms in the covalent compound ethyne is six.
What are covalent bonds?Covalent bond are formed by the sharing of electrons between two atoms.
In ethyne molecule two carbon atoms are present and between two carbon atoms three covalent bonds are present. And each covalent bond is formed by the sharing of two electrons. So three covalent bonds are formed by the sharing of 6 electrons.
Hence in ethyne 6 electrons are being shared.
To know more about covalent bond, visit the below link:
https://brainly.com/question/12732708
#SPJ2
What is the formula for nickel || dichromate
Answer: Cr2NiO7 is the molecular formula for nickel II dichromate.