Isotopes : the same atomic number, but different mass numbers
Atomic mass is the average atomic mass of all its isotopes
avg atomic mass = m1.%m1 + m2.%m2....mn.%mn
You did not include the mass of each isotope
Element X :
X-23 = 41.9%
X-25 = 58.1%
The average atomic mass of Element X :
[tex]\tt =0.419\times mass~X-23+0.581\times mass~X-25[/tex]
What is the what is what and why
Answer:
what
Explanation:
is this free points
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For the first question:
Use the formula: Density = Mass/Volume
Given in the question:
Mass - 1800 mg
Volume - 2 cm3
Calculation
Density = Mass/Volume
= 1800/2
= 900mg/cm3
Therefore, the density is 900mg/cm3.
can someone help and lmk if my answers are correct i don’t think they are please help i’ll give brainliest thank you
Answer:
5=C, every action has an equal or opposite reaction,
6=B, since it has less air drag and more force exerted on it
7= You're correct
In the early 1900's many scientists thought that an atom consisted of a positive substance with negative charges scattered throughout the substance. Then Ernest Rutherford completed an experiment that changed the concept of an atom. His discovery led to the understanding that an atom. His discovery led to the understanding that an atom consists of mostly empty space with
The question is incomplete; the complete question is;
In the early 1900s many scientists thought that an atom consisted of a positive substance with negative charges scattered throughout the substance. Then Ernest Rutherford completed an experiment that changed the concept of an atom. His discovery led to the understanding that an atom consists mostly of empty with space with-
Protons orbiting a dense nucleus made of electrons and neutrons
Electrons orbiting a dense nucleus made of protons and neutrons
Neutrons and protons orbiting a cloud of electrons
Electrons and protons orbiting a cloud of neutrons
Answer:
Electrons orbiting a dense nucleus made of protons and neutrons
Explanation:
Rutherford established the nuclear theory of the atom by his famous experiment. In his experiment, alpha particles were used to bombard a thin gold foil and the movement of the particles was observed on a moveable zinc sulphide screen.
It was discovered from the experiment that the atom was mostly made up of empty space. The electrons orbit a dense nucleus comprising of protons and neutrons.
What can you infer on the materials that clings unto the magnets? What made you say so?
How do scientist determine the ages of fossils
Answer:
Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages. Absolute dating is used to determine a precise age of a fossil by using radiometric dating to measure the decay of isotopes, either within the fossil or more often the rocks associated with it.
Please help me answer this chemistry question:
how many atoms are there in 6.8 mole of boron
There are many types of forces. Which statement best compares an electrical force to gravitational force?
A. Electrical forces hold small objects near eachother and gravitational forces hold large objects near each other.
B. Electrical forces depends on the type of charge and gravitational forces depend on the mass of the objects and how far apart they are.
C. Electrical forces are attractions between similar types of charges and gravitational forces are attractions between similar size of objects.
D. Electrical forces require that the objects are in contact with eachother and gravitational forces require the objects are far from each other.
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How many ATOMS of sulfur are present in 3.07 grams of sulfur hexafluoride ?
Sulfur tetra flouride formula is SF4 so there are 3.07 moles of sulfur ATOMS in there.
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Why do nitrogen molecules have triple bonds, whereas oxygen molecules have double bonds? How many valence electrons does each atom have, and how does that affect the type of bond formed in each molecule? Draw Lewis dot diagrams to support your answer
Answer:
Nitrogen is a diatomic molecule in the VA family on the periodic table. Nitrogen has five valence electrons, so it needs three more valence electrons to complete its octet. A nitrogen atom can fill its octet by sharing three electrons with another nitrogen atom, forming three covalent bonds, a so-called triple bond.
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Answer:
Two covalent bonds form between the two oxygen atoms because oxygen requires two shared electrons to fill its outermost shell. Nitrogen atoms will form three covalent bonds (also called triple covalent) between two atoms of nitrogen because each nitrogen atom needs three electrons to fill its outermost shell.
The number of electrons in an atom's outermost valence shell governs its bonding behaviour. Elements whose atoms have the same number of valence electrons are grouped together in the Periodic Table. ... To form a covalent bond, one electron from the halogen and one electron from another atom form a shared pair.
science , thank you for helping !!
Answer:
sksksk
Explanation:
anna oop
Answer:
Try putting Dd okkkkkkkk
12. Several isotopes of a certain atom "X" exist. 4.35% of all X atoms have a mass of 39.946 amu.
83.79% have a mass of 41.941 amu, 9.50% have a mass of 42.941 amu, and 2.36% have a mass of
43.939 amu. What is the average atomic mass of atom X?
Answer: 41.97
Explanation:
which ion has the smallest radius
Where is most of the mass of an atom located? O it is split between the nucleus and the orbits Oin the electrons Oin the nucleus Oin the orbits
Answer:
In the nucleus.
Explanation:
2. How much ice will 7 cups of water make?
Answer:
6.44 cups of ice
Explanation:
The ratio of the densities is simply the density of one divided by the density of the other: The density of ice to water is 0.92. Using the ratio, one can simply multiply the volume of the ice by 0.92, which is the conversion factor for the volume of ice to liquid water.
7 × 0.92 = 6.44
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What is methane? Where is it found?
Answer:
Methane is an odorless, colorless, flammable gas. It is used primarily as fuel to make heat and light. It is also used to manufacture organic chemicals. Methane can be formed by the decay of natural materials and is common in landfills, marshes, septic systems and sewers
Explanation:
What is the mass of an unknown object that has a volume of 20 mL and density of 3.5 g/mL?
Answer:
70
Explanation:
density=mass/volume
therefore mass = density*volume
20*3.5=70
what is physical and chemical change ?
Answer:
Physical change is there is a difference in appearance, smell, etc.
Chemical change is there is change in the composition or the rearrangement of the atoms of one or more substances.
When you are done looking at slides of blood smears you should _____.
1 wash the slides off in the sink
2 leave the slides for someone else to clean up.
3 dispose according to your teacher’s instructions
4 dump in the trash
pls help
Answer:
Hello!!! Princess Sakura here ^^
Explanation:
The answer is Choice 3. the teacher will give you the most safe instructions according to how dangerous the blood might be.
What type of heat is used to cook pancakes?
Answer choices :
A. Conduction
B. Convention
C. Radiation
Answer:
A
Explanation:
Answer:
conduction (A) is the right answer
All atoms of the same element:
have the same number of atoms
have the same number of neutrons
have the same number of electrons
have the same number of protons
Answer:
have the same number of protons
Explanation:
The number of protons in an atom determine what element it is. The number of electrons and neutrons can vary from atom to atom of the element, as long as all the atoms have the same number of protons.
1 pt
Question 5
Aurora records the following observations: It rained on Monday. It was sunny on
Tuesday. It rained again on Wednesday: What is Aurora recording?
A) weather
B) neither weather or climate
C) both weather and climate
D) climate
Answer: D. Climate
Explanat
Plz help getting timed
Answer:
I think the first one is Active Transport.
Explanation:
The second one is passive transport
Good scientists have what characteristics in common?
Answer:
determination or brains
Explanation:
Which substance gets broken down in a homogeneous mixture?
colloid
solution
solute
solvent
Answer:
Should be Solute
Explanation:
I looked it up ;)
Answer:
c. Solute
Explanation:
How many moles of Magnesium are present in 0.478 g of the element?
(Atomic mass: Mg-24 u)
Answer:
0.0199moles
Explanation:
The number of miles of a substance can be calculated using the formula:
Number of moles (n) = Mass (M) / Molar mass (MM)
In this question, the mass of Magnesium element (Mg) = 0.478 g while the atomic mass is 24
Therefore, number of moles of Magnesium is:
Moles = 0.478/24
Moles = 0.01992
Hence, 0.0199 moles of Magnesium are contained in 0.478 g of the element.
calculate the mass of onygen gas whose
volume is 320mL at 17 degree celsius and 2 atm Pressure
Answer:
The mass of oxygen gas is 0.96 g.
Explanation:
Given data:
Mass of oxygen gas = ?
Volume of as = 320 mL (320mL × 1L /1000 mL = 0.32 L)
Temperature of gas = 17 °C
Pressure of gas = 2 atm
Solution:
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
Now we will convert the temperature.
17+273 = 290 K
Now we will put the values in formula.
2 atm × 0.32 L = n × 0.0821 atm.L/ mol.K × 290 K
0.64 atm.L = n × 23.81 atm.L/ mol.
n = 0.64 atm.L / 23.81 atm.L/ mol.
n = 0.03 mol
Mass of oxygen:
Mass = number of moles × molar mass
Mass = 0.03 mol × 32 g/mol
Mass = 0.96 g
The mass of oxygen gas is 0.96 g.
The mass of oxygen will be "0.96 g".
Given:
Volume,
V = 320 mLor,
= 0.32 L
Temperature,
T = 17°Cor,
= 290 K
Pressure,
P = 2 atmGeneral gas constant,
R = 0.821 atm.L/mol.KAs we know the formula,
→ [tex]PV = nRT[/tex]
By substituting the values, we get
[tex]2\times 0.32=n\times 0.0821\times 290[/tex]
[tex]0.64=n\times 23.81[/tex]
[tex]n = \frac{0.64}{23.81}[/tex]
[tex]= 0.03 \ mol[/tex]
hence,
→ Mass of oxygen = [tex]Number \ of \ moles\times Molar \ mass[/tex]
= [tex]0.03\times 32[/tex]
= [tex]0.96 \ g[/tex]
Thus the above answer is right.
Learn more:
https://brainly.com/question/14049502
How do you call when a substance goes from a solid to a liquid?
Answer:
Melting point as a chemistry concept
The solid begins to go from a solid state to a liquid state — a process called melting. The temperature at which melting occurs is the melting point (mp) of the substance.