A physical change to a substance
can never be reversed
increase or decrease the mass of a substance
changes to type of matter the substance is made of
changes one or more of the physical properties of a substance
Answer:
4th one
Explanation:
a physical change is something u can see, so if the substance changes its properties then thats a physical change.
See photo! Calculating mass and percentage yields.
Answer:
see above
Explanation:
check for cfe's
1.25 x 10^25 atoms of magnesium = ? moles of magnesium
"pure water does not conduct electricity. But some tap water probably can. Which best explains this?" a . Tap water is H20 b . Pure water is H20 c . Some tap water has minerals, such as iron in it.
Explanation:
"pure water does not conduct electricity. But some tap water probably can."
The reason why pure water does not conduct electricity is due to the absence of mineral and metal containing salts. Pure water is made up of only Hydrogen and oxygen atom as represented by the formula; H2O
Tap water on the other hand are most likely able to conduct electricity due to the presence of these ions. They may arise from impurities or during treatment processes.
The correct options are;
b . Pure water is H2O
c . Some tap water has minerals, such as iron in it.
1. A wave has a frequency of 800 Hz and a wavelength of 2000 cm. What speed
is this wave traveling?
Answer:
V=f*(wavelength)
V= (800)(20m)
16000m/s
Explanation:
i need help with d and e
Answer:
D: False
E: Ethane
Explanation:
if 13 moles of Fe react, what is the mass of FeS produced?
Answer:
1144 g of FeS
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
Fe + S —> FeS
From the balanced equation above,
1 mole of Fe reacted to produce 1 mole of FeS.
Therefore, 13 moles of Fe will also react to produce 13 moles of FeS.
Finally, we shall determine mass of 13 moles of FeS. This can be obtained as follow:
Mole of FeS = 13 moles
Molar mass of FeS = 56 + 32
= 88 g/mol
Mass of FeS =?
Mass = mole × molar mass
Mass of FeS = 13 × 88
Mass of FeS = 1144 g
Therefore, 1144 g of FeS were obtained from the reaction.
An alpha particle is composed of He2+ ions?
true or false
Answer: The given statement is False.
Explanation:
Alpha particle is a helium nuclei.
Alpha particles are produced when a larger nuclei decays into smaller nuclei in radioactive decay. Alpha particles have mass number and atomic number as 4 and 2 respectively.
General representation of alpha decay :
[tex]^A_Z\textrm{X}\rightarrow ^{A-4}_{Z-2}\textrm{Y}+^4_2\textrm{He}[/tex]
Thus the given statement that alpha particle is composed of [tex]He^{2+}[/tex] ions is False.
The statement of [tex]\rm He^2^+[/tex] ions has formed the alpha particles is true.
Alpha particles are particles that have been similar to the He-4, with the presence of two protons and two neutrons. The alpha particles have the absence of electrons and have been formed during the alpha decay.
[tex]\rm He^2^+[/tex] has been the ion of He with the positive charge indicating the loss of 2 electrons. Thus, in [tex]\rm He^2^+[/tex], there has been 2 protons, 2 neutrons, and 0 electrons.
The atomic configuration of [tex]\rm He^2^+[/tex]has been similar to the alpha particles. Thus, the statement stating, "the alpha particles to be composed of [tex]\rm He^2^+[/tex]ions " is True.
For more information about the alpha particles, refer to the link:
https://brainly.com/question/1685421
classify the following elements under metals, non metals and metalloids, boron, zinc Mercury, silicon, oxygen, nitrogen, sodium
Answer:
Zinc mercury transition metal
Silicon boron metalloid
Oxygen nitrogen non metal
Sodium alkali metal
Explanation:
Two rocks one weighing 100m and the other weiging 200n are drpped from a 50-m cliff at the same time when both rocks are 10m from the ground and air friction is ignored which is the same
Answer:
Ignore all friction
Directions Identify the reactants and product in the following reaction.
4A1+302 → 2A1203
When collecting temperature as a function of time for the reaction of KOH with HCL, which time is most significant
Answer:
At the completion of reaction.
Explanation:
The time when the reaction take places is the most significant time for measuring temperature of the solution because on this time the temperature will decrease or increase. Some reactions releases heat energy upon completion we called them exothermic reactions whereas some absorb heat energy from the surrounding, decreases the temperature which is known as endothermic reaction so measuring temperature at the completion of reaction is the correct time.
Pls help will give brainlist
Answer:
D. 5
Explanation:
The coefficient will almost always be the whole number in front of the variable.
example
5(x)= 7
The coefficient would be 5.
En una planta de energía, se produce CO2 gracias a la reacción de combustión del material orgánico con oxígeno para producir CO2, SO2, SO3, NO, NO2 y H2O que son los causantes del efecto invernadero, el SO2 reacciona con H2O para formar H2SO3, causante de la lluvia ácida. En condiciones de gas ideal el SO2 se encuentra a una temperatura de 100°C y 0,5 atm de presión, el volumen ocupado generalmente es de 25 L. 5. La ecuación para hallar el número de moles debe ser: a. Gases ideales: relación entre todas las variables que influyen sobre los gases b. Boyle: relación entre volumen y presión c. Charles: relación entre el volumen y la temperatura d. Gay Lussac: relación entre la presión y la temperatura
Answer:
a. Gases ideales: relación entre todas las variables que influyen sobre los gases
Explanation:
La ecuación del gas ideal da la relación entre las variables; presión, volumen, temperatura y número de moles.
Según la ecuación del gas ideal; PV = nRT
P = presión del gas
V = volumen del gas
n = Número de moles del gas
R = constante de gas
T = temperatura del gas
El número de moles de SO2 se obtiene de;
n = PV / RT
n = 0,5 * 25 / 0,082 * 373
n = 12,5 / 30,586
n = 0,41 moles
Which substances in the list can be used to write a complete combustion reaction? (4 points)
O 1, 2, and 3
O 2, 3, and 6
O 1, 4, and 5
O 1, 2, and 5
Answer:
B. 2, 3 and 6
Explanation:
The primary materials for a chemic combustion reaction are Fuel + O2 → CO2 + H2O!
Hope this could help! （*＾ワ＾*）
Answer:the answer is B
Explanation:
How many grams are found from 2 moles of glucose C6H1206?
Answer:
360g
Explanation:
Hope it helps you!
The number of protons is equal to
a the number of neutrons.
b the atomic mass.
c the number of electrons.
d the atomic number.
Answer:
c the number of electrons
40 points plz help quick!! Order the interactions from strongest to weakest.
1. Covalent Bond
2. Ionic Bond
3. Dipole-Dipole Interactions
4. Hydrogen Bond
5. Dispersion forces
Answer:
2,5,4,1,3
Explanation:
Answer:
Ionic Bond
Explanation:
what are the difference between hemogeneous mixture and heterogeneous mixture ??
Answer:
Refer to attached file below
Hope it helps..
Have a great day :P
list 2 ways mechanical energy can be transformed into non-mechanical energy ?
Answer:
One is the classic example of friction. When two surfaces rub together, they generate thermal energy, or heat. This is a transformation of the mechanical kinetic energy of the objects into the thermal non-mechanical energy (which is small-scale kinetic energy).
Mechanical energy can be used to overcome friction or lost in form of heat in machine parts. Friction and heat are two non-mechanical energy.
Transformation of mechanical energy into non mechanical energy
Based on the principle of conservation of energy, energy can neither be created nor destroyed but can be transformed from one form to another.
Two ways mechanical energy can be transformedThe two ways mechanical energy can be transformed include the following;
FrictionHeatMechanical energy can be used to overcome friction or lost in form of heat in machine parts, in this process, the mechanical energy (kinetic energy) would be converted into other forms of energy such as heat.
Learn more about conservation of energy here: https://brainly.com/question/166559
:)
Why is water called.compound
Answer:
because it's composed of two elements, hydrogen and oxygen. water is technically a molecular compound tho, for it has two hydrogens.
If magnesium and nickel were used as electrodes to construct an electrochemical cell like the one shown at right, which metal would form the anode and which the cathode?
anode:
cathode:
Answer:
anode: magnesium
cathode: nickel
Explanation:
edg. 2021
Calculate the concentration of a 220 g solution of calcium chloride (CaCl2) that has a volume of 11 L
Answer: The concentration of the solution is 0.18 M
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
[tex]Molarity=\frac{n}{V_s}[/tex]
where,
n = moles of solute
[tex]V_s[/tex] = volume of solution in L
moles of [tex]CaCl_2[/tex] = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{220g}{111g/mol}=1.98mol[/tex]
Now put all the given values in the formula of molality, we get
[tex]Molarity=\frac{1.98mol}{11L}=0.18M[/tex]
Therefore, the concentration of the solution is 0.18 M
A mixture of helium, nitrogen and oxygen has a total pressure of 781 mmHg. The partial pressure of helium is 331 mmHg, and the partial pressure of nitrogen is 222 mmHg. What is the partial pressure (in mmHg) of oxygen in the mixture?
Answer:
Partial pressure of O₂ = 228 mmHg
Explanation:
The mixture is made of three gases, He, N₂ and O₂.
Total pressure of it, is 781 mmHg.
There is a law from gases, that indicates the sum of partial pressures of each gas in a mixture will be the total pressure of the system. In conclussion:
Partial pressure of He + Partial pressure of N₂ + Partial pressure of O₂ = Total pressure.
331 mmHg + 222 mmHg + Partial pressure of O₂ = 781 mmHg.
Partial pressure of O₂ = 781 mmHg - 331 mmHg - 222 mmHg
Partial pressure of O₂ = 228 mmHg
True or False; the atomic number always equals the number of protons, neutrons and electrons found in an atom.
"" ANSWER""
Protons are values of atomic numbers that do NOT change, that is, they are located inside the nucleus of the atom, whereas electrons are located in the electrosphere that can gain or lose electrons, the electron has a negative charge and the Proton positive, that is, if in any atom it wins an electron the atom will be negative and if the atom loses it will be positive because we already know that the number of protons does not change. To calculate the number of neutron we have to make the number of rounded atomic mass which becomes mass less the number of protons for example oxygen gas has 8 protons which is the atomic number and has atomic mass 15,999 which rounding up to 16 to find the number of neutrals we do 16-8 = 8 so now we know that oxygen has: 8 protons, 8 electrons and 8 neutrons but the values will not always be the same but the possibility of protons and neutrals having the same value is 75% by my count .
● ○ ● RULES ○ ● ○ ●
Atomic number = number of protons
Atomic mass ROUNDNESS = mass
Number of neutrons = number of protons - mass number
OBSERVATION- EXPLANATION FOR STUDENTS OF 9 YEARS BECAUSE IN THE HIGH SCHOOL UP SOME CHANGES CHANGE.
■■ GOOD STUDIES ■■
Can someone tell me if these are right? I am supposed to be decoding this for my escape room but it seems to be wrong.
Answer:
Q1 is A.
Q2 is right
Q3 is D.....I dont
really know about this one
Q4 is right
I need help with the balancing one
Answer:
2Na2S + Cd(NO3)2 ---> CdS + 2NaNO3
The coefficients therefore are 1,1,1&2
What does chemistry mean?
Answer:
The definition of chemistry is a branch of science that deals with the form and properties of matter and substances or the interaction between individuals.
two types of subatomic particles in the nucleas of an atom
Explanation:
protons and neutrons.....
...
Answer:
The subatomic particles are Protons and Neutrons.
Living organisms need energy to carry on their life processes. Photosynthesis is a process that allows for photosynthesizing organisms, such as algae and green plants, to produce their own materials for energy production and survival. This process can be outlined as a simplified chemical equation containing reactants (goes into the process) and products (made/comes out of the process).Using your knowledge of science and figures above, select the choice that accurately expresses photosynthesis.
the correct combo is C
We know sunlight is key factor in photosynthesis so A and D are out.
we also know plants get their bulk by breaking up co2 and using the carbon which releases oxygen as a byproduct so B is also out of the question.