A student calculates the density of an unknown metal sample to be 8.25 g/cm3
Which set of data from the student's notebook correctly calculates the density of her unknown metal sample?
A
Mass = 165.2 g, Volume = 21.2 cm3
В.
Mass = 198.0 g. Volume = 24.0 cm3
С
Mass = 82.5 g. Volume = 11.0 cm3
D.
Mass = 202.5 g. Volume = 25.0 cm3
Answers
Answer:
the answer is b
Explanation:
mass=198 divided by volume 24 gives you 8.25
Related Questions
help me please i put nine points!
Answers
Answer:
eons.
It would be D. An eon.
12.4 g of phosphorus reacts with 9.6 g of oxygen.
Which of the following chemical equation represents this reaction?
[Relative atomic mass: P, 31; 0, 16]
A P + O2 + PO2
B 2 P + O2 + 2 PO
C 3P +2 02 → P304
D 4P +3 02 → 2 P203
Answers
Answer:
D 4P +3O₂ → 2 P₂O₃
Explanation:
In this problem, we need to convert the mass of phosphorus and oxygen to moles trying to find the ratio of reaction (The moles of P that reacts per mole of O₂):
Moles P:
12.4g P * (1mol P / 31g) = 0.4 moles
Moles O₂:
9.6g * (1mol / 32g) = 0.3 moles
The ratio of reaction is:
0.4 mol / 0.3 mol = 1.33 = 4 moles of P / 3 moles of O₂
That means 4 moles of P react with 3 moles of O₂ and the reaction that represents this ratio is:
D 4P +3O₂ → 2 P₂O₃The reaction of 12.4 g Phosphorous with 9.6 grams of Oxygen will be represented as [tex]\rm 4\;P\;+\;3\;O_2\;\rightarrow\;2\;P_2O_3[/tex]
In a chemical equation, the stoichiometric values are the moles of the molecules involved in the reaction. For the reaction of Phosphorous and oxygen, the moles of both elements are to be calculated.
Moles = [tex]\rm \frac{weight}{molecular\;weight}[/tex]
Moles of Phosphorous = [tex]\rm \frac{12.4}{31}[/tex]
Moles of Phosphorous = 0.4
Moles of oxygen = [tex]\rm \frac{9.6}{16}[/tex]
Moles of oxygen = 0.6
Moles of [tex]\rm O_2[/tex] = 0.3
The equation will be:
[tex]\rm 0.4\;P\;+\;0.3\;O_2\;\rightarrow\;2\;P_2O_3[/tex]
[tex]\rm 4\;P\;+\;3\;O_2\;\rightarrow\;2\;P_2O_3[/tex]
The correct reaction will be D.
For more information about the chemical equation, refer the link:
https://brainly.com/question/1689737?referrer=searchResults
Please help me choose the correct statement
Answers
What type of chemical bonding would exist between H-C-H?
Answers
Answer:
covalent bond
Explanation:
What conclusion can she make from her experiment?
Heather is testing a substance as to whether it is
organic or inorganic. She works with the solid
substance and discovers it can conduct electricity
without burning. She also knows the carbon to oxygen
ratio is 1 to 2
O The substance is organic because it is solid at room
temperature.
O The substance is organic because it cannot burn
readily
O The substance is inorganic because it has carbon.
The substance is inorganic because it conducts
electricity
Answers
Answer:
Im pretty sure the answer is D
Explanation
Answer:
Answer D
Explanation:
Considering 2N2H4(g) + N2O4(g) -> 3N2(g) +4H2O(g)
How many grams of N2H4 will be needed to produce 121.3g of H2O
Answers
Answer:
107.8
Explanation:
64 gram of N2H4 produce 72 gram of H20
then by crossmultiplication
64*121.3/72=107.82
When an atom becomes an ion, the number is written as a blank
Answers
when an atom loses a valence electron, it loses a negative charge. it becomes a ... Formulas: for an ionic compound, write the symbol of the positive ion and then
Which substance is correctly identified as a homogeneous or heterogeneous mixture?
A. salad -- heterogeneous
B. milk --- heterogeneous
C. river water --- homogeneous
D. beach sand --- homogeneous
Answers
Answer:
A
Explanation:
A salad with lettuce, cheese, seeds, tomatoes, broccoli, and other vegetables is an example of a heterogeneous mixture.
Milk is not mixed with anything so that is incorrect
River water is mixed in with dirt and minerals so this one is incorrect
Beach sand is incorrect because you can see colored particles.
Is 2CO + O2 -> 2CO2 A balanced or unbalanced equation
Answers
Answer:
It is balanced.
Explanation:
You have the same amount of atoms on both sides. 2 carbon and 4 oxygen.
SOMEONE PLEASE HELP ME! provide explanations please
Answers
Answer:
hope this document helps! it's kinda hard to type out the explanation but ill try
Explanation:
divide the percenatge by the molar mass of the element.
(do this for both elements) \
find the lowest number and divide the results with it
now you have your empirical formula (with the rounded answers)
then find the molar mass of your empirical formula
divide the number given (267) by the molar mass to get a rounded number.
multiply that rounded answer to your empirical formula to get your empirical formula. :)
What property would you use to describe Oxygen and Hydrogen in their natural form?
Answers
Answer:
At standard temperature and pressure, hydrogen is a colorless, odorless, and tasteless gas. Hydrogen is very flammable and burns with an invisible flame. It burns when it comes into contact with oxygen. The byproduct of a hydrogen and oxygen explosion is water or H2 O.
A reaction balanced when it shows us the_____ number of atoms are present before and after the reaction.
Answers
Answer:
equal
Explanation:
According to the law of conservation of matter, the number of atoms before and after a chemical reaction should be equal, such that no atoms are, under normal circumstances, created or destroyed.
What are the chemical properties of iron meta
Answers
Answer:
Physical properties
Atomic mass: 55.845
Density: 7.87 g/cm3
Group: Transition metals
Electrons: [Ar] 3d6 4s2
Melting point: 1811 K
Boiling point: 3134 K
Discovered: Ancient times
Explanation:
hope this helps! :D
Vanadium has an atomic mass of 50.9415 amu. It has two common isotopes. One isotope has a mass of 50.9440 amu and a relative abundance of 99.75 %.
What is the abundance of the other isotope?
What is the mass of the other isotope?
Answers
Answer:
Average atomic mass of the vanadium = 50.9415 amu
Isotope (I) of vanadium' s abundance = 99.75 %= 0.9975
Atomic mass of Isotope (I) of vanadium ,m= 50.9440 amu
Isotope (II) of vanadium' s abundance =(100%- 99.75 %) = 0.25 % = 0.0025
Atomic mass of Isotope (II) of vanadium ,m' = ?
Average atomic mass of vanadium =
m × abundance of isotope(I) + m' × abundance of isotope (II)
50.9415 amu =50.9440 amu× 0.9975 + m' × 0.0025
m'= 49.944 amu
Explanation:
The abundance of the other isotope is 0.25% and the mass of the other isotope is 49.944 amu.
What is the natural abundance of elements?Natural abundance can be described as the abundance of isotopes of a chemical element naturally found on a planet. The relative atomic mass of these isotopes is the atomic weight of the element in the modern periodic table.
The abundance of an isotope can vary from planet to planet but remains relatively constant in time. The natural abundance of an isotope can be affected by the probability of its creation in nucleosynthesis and by the production of a given isotope as a daughter of the natural radioactive isotope.
Given, the average atomic mass of Vanadium = 50.9415 amu
The mass of one isotope = 50.9440 amu, relative abundance =99.75 %.
The relative abundance of the other isotope = 100 - 99.75 = 0.25 %
50.9415 = 50.9440 × 0.9975 + 0.0025 × M
Mass of other isotope = 49.944 amu
Learn more about natural abundance, here:
https://brainly.com/question/5087395
#SPJ2
What must happen for an electron to become excited?
An electron must absorb light energy
An electron must release light energy
Answers
Which equation is correctly balanced?
Answers
Answer:
C
Explanation:
pls help question 2 ill attach a picture
Answers
Answer:
X 154
Check solution in explanation
Explanation:
Average atomic mass = ( mass 1× abudance) + ( mass 2× abudance)+ ( mass 3× abudance) / 100
(149×13.8)+(152×44.9) +(154×41.3)/100
2056.2 + 6824.8 + 6360.2/100
=152.412
During a chemical or physical change, energy may be...
a. created into another form
b. destroyed and reinvented into another form
c. converted into another form
d. disappeared
Answers
Answer: C: Converted into another form
Explanation: pues es esa calale y si va a hacer
During a chemical or physical change, energy is converted to another form. Energy cannot be created or destroyed. During a chemical reaction, physical change the energy and mass are conserved.
What is law of conservation of energy ?According to the law of conservation of energy energy can neither be crated nor be destroyed. Hence, the total energy of a system is always conserved.
However, energy can be transformed from one form to the other. Therefore, the energy lost in one form is gained in another form. For example, in all electrical devices, the electrical energy is converting to other forms of energy such as light, thermal , mechanical etc.
Similarly, during a chemical reaction, the energy released by a reaction system is equal to the energy absorbed by other reacting system. Similarly in electrochemical cells the chemical energy is converting to electrical energy.
Find more on energy transformation:
https://brainly.com/question/17589256
#SPJ6
Calculate the number of protons and neutrons for ²⁴Mg and 88Sr.
Answers
Answer:
12 protons and 12 neutrons are present in Mg and
38 protons and 50 neutrons are present in Sr
Explanation:
Answer:
For ²⁴Mg
1. Proton number = 12
2. Neutron number = 12
For ⁸⁸Sr:
1. Proton number = 38
2. Neutron number = 50
Explanation:
For ²⁴Mg:
1. Determination of the number of proton.
The atomic number of an element is simply defined as the number protons in the atom of the element. The atomic number of ²⁴Mg is 12 since no two elements have the same atomic number.
Atomic number = 12
Proton number = Atomic number
Proton number = 12
2. Determination of the Neutron number.
Mass number = 24
Proton number = 12
Neutron number =?
Mass number = Proton + Neutron
24 = 12 + Neutron
Collect like terms
Neutron = 24 – 12
Neutron number = 12
For ⁸⁸Sr:
1. Determination of the number of proton.
The atomic number of ⁸⁸Sr is 38.
Atomic number = 38
Proton number = Atomic number
Proton number = 38
2. Determination of the Neutron number.
Mass number = 88
Proton number = 38
Neutron number =?
Mass number = Proton + Neutron
88 = 38 + Neutron
Collect like terms
Neutron = 88 – 38
Neutron number = 50
FULL TITUIE Lait veluw. How Element Valence Electrons electrons Gain / lose Symbol and Charge Cation or Anion Metal, Nonmetal, or Metalloid many Calcium 1+ loso 2 ca? cation Metal Bromine Nitrogen Iron (111) 3 Tin (II) 2 Fluorine Cesium lodine Phosphorus Copper (1) Lithium Aluminum Sulfur Manganese (IV) 4 Chlorine Oxygen
Answers
Answer:
Can you translate to english? but i think its X
Explanation:
Which substances have AHp = 0 kJ/mol by definition?
Answers
Answer:
4
Explanation:
i think
what is ideal gas constant?? g0ogle doesnt got any good answerss
Answers
Answer:
An ideal gas is a gas with particular characteristics.
Explanation:
The particles have no volume All collisions between particles are elastic collisions and lose no kinetic energy The particles neither attract each other nor repel They have random movementIdeal gases are hypothetical which means that they do not exist in their true form.
hope this helps, pls mark brainliest :D
Help meeee I don’t understand
Answers
Answer:
unbalanced moving to the right is the awnser
Answer:
unbalanced moving to the right i think
Explanation:
A molecule of __________ consists of two atoms of hydrogen and one atom of oxygen.
The chemical formula for water is __________.
Each hydrogen atom in a water molecule shares __________ valence electron(s) with the oxygen atom.
The chemical formula for carbon dioxide is __________.
The chemical formula CO represents the compound __________.
Atoms or ions in compounds are held together by chemical __________.
Three types of chemical bonds are covalent, ionic, and __________ bonds.
Answers
Answer:
WaterH2Oone pairCO2Carbon monoxide bondsmetallicAnswer:
A molecule of Water consists of two atoms of hydrogen and one atom of oxygen.
The chemical formula for water is H2O .
Each hydrogen atom in a water molecule shares one valence electron(s) with the oxygen atom.
The chemical formula for carbon dioxide is CO2 .
The chemical formula CO represents the compound carbon monoxide.
Atoms or ions in compounds are held together by chemical bond.
Three types of chemical bonds are covalent, ionic, and metallic bonds
An object has a density of 1.4 g/cm . It is slowly lowered into a graduated cylinder whose water level was 65 mL. When the object is completely submerged the water level rises to 90 mL. What is the mass of the object?
Answers
Answer:
Explanation:
Weight
A measure of the force of gravity on an object
Mass
The measurement of how much matter an object contains
Volume
The amount of space that matter occupies
Density
The physical property that relates the mass and volume of an object or material
Unlike weight, mass doesn't change with location, even when the force of gravity on an object changes
Why do scientists prefer to describe its matter by its mass rather than its weight?
International System of Units
What system of units do scientists use to measure the properties of matter?
Liter, milliliter, cubic centimeter
3 common units of volume
Volume= length•width•height
Volume formula
Sand and feathers have different densities
Why does a kg of sand take up much less space than a kg of feathers?
Density=mass/volume
Density formula
Objects with densities greater than water will sink and objects with densities less than water will float. The density of wood is less than water (1 g/cm3) and the density of iron is greater than water (1 g/cm3)
If you drop a block of iron and block of wood into water, the iron sinks and the wood floats. What can you conclude about the density of iron and wood compared to the density of water?
V=2,400 cm3
A box has a length of 25 cm, a width of 8 cm, and a height of 12 cm. What is its volume?
D= 13.5 g/cm3
A sample of metal has a mass of 94.5 g and a volume of 7 cm3. What is its density?
Mass= density•volume
Mass formula
M= 234.26 g
Corn oil has a density of 6.89 g/cm3. What is the mass of 34.0 cm3 of corn oil?
Yes. No. The pull of gravity is different on the moon.
A solid has a mass of 180. Would the solid have a mass of 180 g on the moon? Would it have the same weight on Earth as on the moon? Explain.
No, because only the mass and volume will change
Will every solid with the same dimensions have the same density?
Grams and kilograms
Common units for mass
Grams per cubic centimeter or grams per cubic milliliter
Common units for density
V= 20 ml
D= 0.75 g/cm3
George put 25 ml of water into a graduated cylinder. After adding a solid object, the water level in the cylinder rose to 45 ml. What is the volume of the object? The object George is examining has a mass of 15 grams. What is the density of the object?
Aria is riding her bike. She is bent slightly over, holding
onto her handlebars. She wants to go faster.
Which best explains what she should do?
She should bend her hips so her head is closer to the
handlebars.
She should sit straight up on the bike, keeping her
arms tight to her body.
She should spread her arms wide while sitting
straight in her seat.
She should flap her arms up and down like a bird.
Answers
Answer:
She should bend her hips so her head is closer to the handlebars.
Answer:
the answer is A did it on edge
Explanation:
SOLVE THIS ASAP!!!!!!!!!
and yes iknow this is not chem don't come at me u_u
Answers
which atmospheric gas is used by plants and given off by animals
Answers
Reaction type
Li + N2
Li3N
Answers
Answer:
Combination or synthesis
Explanation:
The given reaction is:
6Li + N₂ → 2 Li₃N
This reaction is a synthesis or combination reaction. 6 moles of Li combines with nitrogen gas to produce 2 moles of Li₃N.
In a synthesis reaction, two substances combines together to give singular product. The formation of compounds from the union of the constituent elements falls into this category of reaction.Which statement best compares potential and kinetic energy?
Objects always have more potential energy than kinetic energy.
Kinetic energy increases and potential energy decreases when the velocity of an object increases.
Only potential energy decreases when an object’s height increases.
Objects always have more kinetic energy than potential energy.
Answers
Answer:
Its B) Kinetic energy increases and potential energy decreases when the velocity of an object increases.
Explanation:
because i took the test on edge 2020
Taking into account the definition of kinetic, potencial and mechanical energy, the tatement that best compares potential and kinetic energy is: Kinetic energy increases and potential energy decreases when the velocity of an object increases.
Kinetic energyKinetic energy is a form of energy. It is defined as the energy associated with bodies that are in motion.
Kinetic energy is defined as the amount of work necessary to accelerate a body of a given mass and at rest, until it reaches a given speed. Once this point is reached, the amount of accumulated kinetic energy will remain the same unless there is a change in speed or the body returns to its state of rest by applying a force.
The kinetic energy is represented by the following expression:
Ec= ½ mv²
Where:
Ec is the kinetic energy, which is measured in Joules (J).m is the mass measured in kilograms (kg). v is the speed measured in meters over seconds (m/s).Potential energyPotential energy is the energy that measures the ability of a system to perform work based on its position.
Gravitational potential energy is the energy associated with the gravitational force. This will depend on the relative height of an object to some reference point, the mass, and the force of gravity as follow:
Ep= m×g×h
Where:
Ep is the potential energy in joules (J).m is the mass in kilograms (kg).h is the height in meters (m).g is the acceleration of fall in m/s² (approximately 9.81 m/s²).Mechanical energyFinally, mechanical energy is that which a body or a system obtains as a result of the speed of its movement or its specific position, and which is capable of producing mechanical work. Then:
Potential energy + kinetic energy = total mechanical energy
Principle of conservation of mechanical energyThe principle of conservation of mechanical energy indicates that the mechanical energy of a body remains constant when all the forces acting on it are conservative (a force is conservative when the work it does on a body depends only on the initial and final points and not the path taken to get from one to the other.)
Therefore, if the potential energy decreases, the kinetic energy will increase. In the same way, if the kinetics decreases, the potential energy will increase.
Statement best compares potential and kinetic energyTaking into account the definition of kinetic energy, when the velocity of an object increases the kinetic energy increases.
Therefore, considering the principle of conservation of mechanical energy, the potential energy decreases.
So, the correct answer is the second option: Kinetic energy increases and potential energy decreases when the velocity of an object increases.
Learn more about mechanical energy:
brainly.com/question/17809741
brainly.com/question/14567080
brainly.com/question/12784057
brainly.com/question/10188030
brainly.com/question/11962904