Answer:
1/4
Explanation:
How do rock formations move
between Earth's surface and
interior?
calculate the mass of a sample of cobalt containing 3.31x10^22 atoms
Answer:
Mass = 3.24 g
Explanation:
Given data:
Number of atoms of cobalt = 3.31 × 10²² atoms
Mass of cobalt = ?
Solution:
We will calculate the number of moles of cobalt first.
1 mole contain 6.022× 10²³ atoms
3.31 × 10²² atoms × 1 mol / 6.022× 10²³ atoms
0.0549 mol
Mass of cobalt:
Mass = number of moles × molar mass
Mass = 0.0549 mol × 58.93 g/mol
Mass = 3.24 g
What was Bohr's model of the atom?
Answer:
In atomic physics, the Bohr model or Rutherford–Bohr model, presented by Niels Bohr and Ernest Rutherford in 1913, is a system consisting of a small, dense nucleus surrounded by orbiting electrons—similar to the structure of the Solar System, but with attraction provided by electrostatic forces in place of gravity.
Explanation:
Answer:
In atomic physics, the Bohr model or Rutherford–Bohr model, presented by Niels Bohr and Ernest Rutherford in 1913, is a system consisting of a small, dense nucleus surrounded by orbiting electrons—similar to the structure of the Solar System, but with attraction provided by electrostatic forces in place of gravity
calculate the mass of a sample of cobalt containing 3.31x10^22 atoms
Answer:
Mass = 3.24 g
Explanation:
Given data:
Number of atoms of cobalt = 3.31 × 10²² atoms
Mass of cobalt atoms = ?
Solution:
We will calculate the number of moles of cobalt by using Avogadro number.
1 mole contain 6.022× 10²³ atoms
3.31 × 10²² atoms × 1 mol / 6.022× 10²³ atoms
0.549 mol × 10⁻¹
0.0549 mol
Mass of cobalt:
Mass = number of moles × molar mass
Mass = 0.0549 mol × 58.93 g/mol
Mass = 3.24 g
Review the electron configurations of the elements in period 3, from sodium (Na) to argon (Ar). What do you observe?
Answer:
Electronic configuration represents the total number of electrons that a neutral element contains. We add all the superscripts to know the number of electrons in an atom. The electrons are filled according to Afbau's rule in order of increasing energies.
[tex]Na:11:1s^22s^22p^63s^1 [/tex]
[tex]Mg:12:1s^22s^22p^63s^2[/tex]
[tex]Al:13:1s^22s^22p^63s^23p^1 [/tex]
[tex]Si:14:1s^22s^22p^63s^23p^2 [/tex]
[tex]P:15:1s^22s^22p^63s^23p^3 [/tex]
[tex]S:16:1s^22s^22p^63s^23p^4 [/tex]
[tex]Cl:17:1s^22s^22p^63s^23p^5 [/tex]
[tex]Ar:18:1s^22s^22p^63s^23p^6 [/tex]
The last electron enters the third shell in all elements from Sodium to Argon.
Answer: After the 3s sublevel is filled with two electrons, each additional electron goes into the 3p sublevel.
Explanation: plato/ edmentem answer
What is NaCI and what is KBr?
How does mercury move through the ecosystem through excavation?
Answer:
Mercury is released into the environment from many sources. Mercury becomes airborne when rocks erode, volcanoes erupt and soil decomposes. It then circulates in the atmosphere and is redistributed throughout the environment.
I think this is right.
What atom has two energy levels and 6 valence electrons
Answer:
Its oxygen
Explanation:
Look at the 2nd row in the periodic table and the 6th element in the row.
Lithium has 1 valence electron in the 2nd energy level
Beryllium has 2 valence electron in the 2nd energy level
Eventually, u will reach Oxygen with 6
The one above is wrong
What is the gram atomic mass of lithium?
Answer:
It is 7 g in accordance to the periodic table
How many Signifact figures does 0.000300
Answer:
3 significant digits
Explanation:
The first 0 don't count (that's the rule in significant digits). So 3,0,0 are left over. Count them and total will be 3 significant digits. (remember the last zero count if there is a decimal but the first zeros doesn't count even with the decimals)
What is the molar mass of Fe2O3? (with units)
Answer:
159.7 g/mol
Explanation:
The molar mass of Fe2O3 is 159.7 g/mol.
Given the empirical formula of your compound is CH₂, what is the gram formula mass of the empirical formula?
Answer:
14g
Explanation:
The empirical formula of the compound is CH₂ ;
When we are dealing with compounds the gram formula mass or gram - molecular weight is the molar mass of the compound.
It is determined by adding the atomic masses of the components together and then expressed in grams.
Atomic mass of C = 12
Atomic mass of H = 1
Gram formula mass = 12 + 2(1) = 14g
How many moles of magnesium nitrate are produced from 143.2 grams of nitric acid, HNO3?
2HNO3 + Mg(OH)2 = Mg(NO3)2 + 2H2O
Answer:
1.14 mol
Explanation:
Given data:
Mass of HNO₃ react = 143.2 g
Moles of Mg(NO₃)₂ produced = ?
Solution:
Chemical equation:
2HNO₃ + Mg(OH)₂ → Mg(NO₃)₂ + 2H₂O
Number of moles of HNO₃:
Number of moles = mass/molar mass
Number of moles = 143.2 g/ 63.01 g/mol
Number of moles = 2.273 mol
Now we will compare the moles of HNO₃ and Mg(NO₃)₂
HNO₃ : Mg(NO₃)₂
2 : 1
2.273 : 1/2×2.273 = 1.14 mol
Additional Practice Questions
5. If you had a pH of 4.30 in a 5.00 L sample, how many
moles of hydronium do you have?
Moles of hydronium (H₃O⁺) : 2.5 x 10⁻⁴
Further explanationGiven
pH = 4.3
V sample = 5 L
Required
moles of H₃O⁺(hydronium)
Solution
pH = - log [H₃O⁺]
4.3 = - log [H₃O⁺]
[tex]\tt [H_3O^+]=10^{-4.3}~M=10^{-4.3}mol/L[/tex]
Moles of hydronium for 5 L sample :
[tex]\tt 5~L\times 10^{-4.3}mol/L=5.10^{-4.3}moles=2.5\times 10^{-4}~moles[/tex]
2. Which of the following atoms has the smallest atomic radius?
a. Fluorine, F
b. Strontium, Sr
C. Calcium, Ca
d. Gallium, Ga
Answer:
Fluorine.
Explanation:
Fluorine has more protons resulting in a greater nuclear charge, causing a greater attraction for electrons. ... Fluorine has a smaller radius than lithium because of the greater positive charge of the nucleus, pulling electrons and the electron shells in closer.
Krypton is named after the Greek word that means “secret.” Which explains why krypton was most likely given this name?
Krypton is a halogen, so it is a secret element because it is always part of a compound and is difficult to find by itself.
Krypton is a halogen, so it should be kept secret because it is so reactive and toxic.
Krypton is a noble gas, so it was difficult for chemists to find it, as though it was a secret.
Krypton is a noble gas, so it secretly bonds with every type of element without showing it
Answer:
C) Krypton is a noble gas, so it was difficult for chemists to find it, as though it was a secret.
Explanation:
Answer:
C
Explanation:
The measure of angle BAC can be cakulated using the
3,1
What is the measure of angle BAC? Round to the
nearest whole degree.
0°
С
1°
44
A
3.1 in
48°
4.5 in
B
[Not drawn to scale]
By the use of the trigonometric ratios, we have obtained the angle BAC as 44 degrees.
What is a right angled triangle?A right angled triangle is one in which one of the sides of the triangle is at an angle of 90 degrees. We are told to first find x knowing that;
x = sin^-1( 3.1/4.5) = 44 degrees
We can see that by the use of the trigonometric ratios, we have obtained the angle BAC as 44 degrees.
Learn more about right angled triangle: https://brainly.com/question/3770177
lonic bonds DO NOT share electrons.
A:True
B:False
The halogens are the elements of group 17 on the periodic table. Halogens combine easily with elements from group 1. When a halogen reacts with a metal, what type of compound is formed?
A.
potassium
B.
salt
C.
noble gas
D.
alloy
Answer:
it was salt just took it
Explanation:
Halogens are non metals and when a non metals reacts with metals they form an ionic compound by gaining electrons from the metal.
What are ionic compounds?Ionic compounds are formed by electron loss/gain between two atoms. Ionic bond is the strongest type of bond. Ionic bond is formed between metals and nonmetals.
Metals are electron rich and they are electropositive in nature. They lose one more electron when reacted with nonmetals. Nonmetals which are electronegative will gain electron from the metals and form the ionic bond.
Halogens such chlorine, bromine etc are highly electronegative and they form ionic compounds of metals such as sodium, potassium, magnesium etc by losing gaining one electron from the metal. Therefore, when halogens reacts with metals forming ionic compounds.
To refer more on ionic compounds, refer here:
https://brainly.com/question/9167977
#SPJ6
I need help !!!!!!!!!!!!!!!!!!!!!!!!!
Answer:1&4?
Explanation:
If there are only two atoms in a molecule, what would make it nonpolar?
Answer:
In general, if the electronegativity difference between two atoms is less than 0.5, the bond is considered nonpolar, even though the only truly nonpolar molecules are those formed with identical atoms. Nonpolar molecules also form when atoms sharing a polar bond arrange such that the electric charges cancel each other out.
Explanation:
sorry if I'm wrong or if this doesn't help you
A solution containing aluminium ions forms a white precipitate when a few drops of dilute sodium hydroxide solution are added to it. For example, sodium hydroxide solution reacts with aluminium sulfate solution. Sodium sulfate solution and solid aluminium hydroxide form. a Write a word equation for this reaction.
Answer:
See explanation
Explanation:
A word equation tries to depict a chemical reaction in words. Letters rather than only chemical formulas are used to show the reaction equation.
Now we want to write a word equation that shows the reaction of sodium hydroxide solution and aluminium sulphate solution:
Alumunium sulphate + sodium hydroxide ------>Aluminium hydroxide + sodium sulphate
What is the atomic number and name of an element that has 15 protons in its nucleus?
Answer:
phosphorus.
Explanation:
The atomic number of phosphorus is 15 so the protons will be 15.
Answer:
The name is phosphorus and the number of atomic is 15
Explanation:
"The incredible diversity of pterosaurs is perhaps best expressed in one of the
prehistoric flying reptile's most intriguing and mysterious features: the head crest."
What evidence from the text supports the idea that the diversity of pterosaurs is best
expressed in their head crests?
A "Many pterosaurs had flesh-and-bone crests atop their skulls - dramatic
anatomical characteristics whose purpose is still debated by paleontologists."
B "Akin to a rooster's comb, peacock's crown, or the frill on some lizards!
necks, pterosaur crests were prominent anatomical features found across many
species."
C "Pterosaurs crests are thought to have been fairly ubiquitous, appearing in
many groups of pterosaurs from the Triassic (252-201 million years ago)
through the Jurassic (201–145 million years ago) and Cretaceous (145-66
million years ago) periods."
D "Among pterosaur species known to have had crests, there is an amazing
range of shapes and sizes."
Answer:
b
Explanation:
what is elastic force
Answer:
Something that is elastic can return to its original shape after being stretched or compressed. As you stretch or compress an elastic material like a bungee cord or a rubber band it resists the change in shape. It exerts a counterforce in the opposite direction. Now if you pull back the rubber band u are using force now if you let go the force that you used to pull back is transferred into the band snapping and bouncing. This force is called an elastic force.
Answer:
it is something that will return back to shape and being stretched or compressed
What is Mg(HSO3)2????
Answer:
Mg(HSO3)2 is Magnesium bicarbonate.
Answer:
Mg(HSO3)2: Magnesium Hydrogen Sulfite
Explanation:
Sebastian wants to write the chemical formula for phosphorus tetraoxide. He identifies the chemical symbols as P and O. Which additional step will he take in his process?
identify the elements involved as potassium and oxygen
add a subscript of 4 after the O
write the chemical symbols, in order, as OP
use the prefix tetra before oxygen
Answer:
B
Explanation:
add a subscript of 4 after the O
I just took this quiz
The next step Sebastian will take after identifying the chemical symbols is add a subscript of 4 after the O.
What is chemical formula?The chemical formula of a compound shows the arrangement of the constituent atoms in that compound.
According to this question, Sebastian wants to write the chemical formula for phosphorus tetraoxide. He initially identifies the chemical symbols as P and O.
The next step for Sebastian to take is add a subscript of 4 after the O to make the PO4 chemical formula.
Learn more about chemical formula at: https://brainly.com/question/11140581
2. A chemical formula that shows the actual # and kinds of atoms present in one molecule of a compound is called
O A. ionic formula
O B. empirical formula
O C. molecular formula
Question 1
What causes a thermocline?
a decline in the amount of nutrients available
a difference in water temperature
the absence of plankton
nutrients too heavy to rise to the surface
Question 2
Which organism is a kind of phytoplankton?
algae
sea butterfly
copepod
lion’s mane jellyfish
please help!! and try and answer them all, not just one!
Answer:
1) The Difference in water tempture
2) Algae
Explanation:
Have a good day! ∩__∩
Answer:
question 1. thermocline is caused by a difference in water temperature.
question 2. a kind of phytoplankton is algae
explain the difference between positive and negative acceleration
Answer:
Difference between Positive and negative acceleration is that in positive acceleration velocity of a body increases with time, and negative acceleration velocity of a body decreases with the increasing of time.
Explanation:
