Explanation:
The covering of much of the Sahara desert by grasses, trees and lakes was caused bychanges in Earth's orbit around the Sun;changes in vegetation and dust in the Saharawhich strengthened the African monsoon; and increased greenhouse gases, which may imply that anthropogenic global warming could result in a shrinkage ...
Answer:
global warming ,.....
CaO + H2O -> Ca(OH)2
3.50g of Ca(OH)2 was made from 4.20g of CaO? What is the % yield of Ca(OH)2?
The % yield of Ca(OH)₂ : 62.98%
Further eplanationPercent yield is the compare of the amount of product obtained from a reaction with the amount you calculated
General formula:
Percent yield = (Actual yield / theoretical yield )x 100%
An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients
Reaction
CaO + H₂O ⇒ Ca(OH)₂
mass CaO= 4.2 g
mol CaO(MW=56,0774 g/mol) :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{4.2}{56,0774 g/mol}\\\\mol=0.075[/tex]
mol Ca(OH)₂ based on mol CaO
mol ratio CaO : Ca(OH)₂,= 1 : 1, so mol Ca(OH)₂ = 0.075
mass Ca(OH)₂(MW=74,093 g/mol) ⇒ theoretical
[tex]\tt mass=mol\times MW\\\\mass=0.075\times 74,093 g/mol\\\\mass=5.557~g[/tex]
% yield :
[tex]\tt =\dfrac{actual}{theoretical}\times 100\%\\\\=\dfrac{3.5}{5.557}\times 100\%\\\\=62.98\%[/tex]
HELP I HAVE TO SUBMIT IN 5 MINS!!!!!!! :( I HAVE NO IDEA!!!
which of the below would result in rearrangement of atoms at molecular level
a) salt dissolved in water
b) broken tree branches
c) gasoline combusts in an engine
d) steam rising from hot pavement
The best answer is
A) The atoms in the mineral get rearranged
Explanation:
ANSWER ASAP What are the ions present in the compound MgO? * 1
(1 Point)
Mg2+ and O-
Mg2- and O2+
Mg+ and O-
Mg2+ and 02-
Answer:
mg+ and O-
Explanation:
HOPE IT HELPS
someone please give me a sentence using “chemical bond”
Answer:
Rust, iron oxide, is weak mechanically although its chemical bonds are strong.
Explanation:
Calculate the specific heat of glass from the following data. The temperature of a piece of glass with a mass of 65 g increases by 26°C when it absorbs 840 J of heat energy.
Answer:497J/kg/K
Explanation:
Use the equation: Q=mS◇T
According to specific heat capacity, the specific heat of glass is 0.4970 J/gK.
What is specific heat capacity?Specific heat capacity is defined as the amount of energy required to raise the temperature of one gram of substance by one degree Celsius. It has units of calories or joules per gram per degree Celsius.
It varies with temperature and is different for each state of matter. Water in the liquid form has the highest specific heat capacity among all common substances .Specific heat capacity of a substance is infinite as it undergoes phase transition ,it is highest for gases and can rise if the gas is allowed to expand.
It is given by the formula ,
Q=mcΔT
Substituting values in above equation, c=Q/mΔT, C=840/65×26=0.4970 J/gK.
Thus, the specific heat of glass is 0.4970 J/gK.
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#SPJ2
9.25x10^-8 x6.40x10^3 in scientific equation
Answer:
5.92E-4 or 5.92x10^-4
Explanation:
A class investigated the reactivity of four metals by dropping little pieces of the
metals into solutions of their salts.
When there was a reaction they recorded a `Y’, when there was no reaction they
recorded an `N’.
Here is their table of results.From their results, which is the least reactive metal?
The least reactive metal is lead, since it reacted with none of the salt solutions.
If 150 g of sucrose dissolved in a 1.50 L water what is the molarity of a solution
Answer:
0.2923 molar
Explanation:
M = given mass /(molar mass× volume)
150/342(1.5)
150/513
0.2923M
what should we use in soap making process:-
a) potassium hydroxide
b) sodium hydroxide (lye)
Explain why it should be used
Answer:
a) potassium hydroxide
Explanation:
Potassium Hydroxide is a type of lye specifically used to make liquid soap.
Sodium hydroxide(lye) is used to unclog drains.
Hope this helps plz hit the crown :D
I don't know what to do about this now. I like her a lot; I don't want to just give up on this because I see relationship potential with this girl. And I feel she genuinely does enjoy the time she spends with me too.
Answer:
Awe ...
Explanation:
May someone pls help me with this!
Answer:
Explanation:
1. Chemistry
2. Atoms
3. Anode
4. Cathode
Write one paragraph!!!!!reasons why the minimum wage should be increased.
Answer:
There are pros and cons, I will explain mostly pros. After all the pros outweigh the cons.
Explanation:
Increasing the minimum wage can be letting people work less or earn more. This can have a major impact on the economy in America. It can reduce poverty within some families households. A con concerning this though is that people who work for low pay can lose their jobs and their family can become poor. It can also affect the federal minimum wage.
Hopefully this helped you out a lot. Please make sure to make my answer brainliest. Have a great rest of your day or night
Answer:
Minimum wage increases allow people to work less and earn more. This may have a significant influence on the American economy. It can help some families get out of poverty. People who labor for little compensation risk losing their employment and being unable to provide for their families, which is a drawback. As a result, the federal minimum wage may also be affected.
Explanation:
plzzz brainlest
4. Why does liquid water take on the shape of a cup it is poured into, but solid ice cubes do
not?
A. liquid water molecules are softer than solid ice molecules
B. liquid water molecules are smaller than solid ice molecules
C. liquid water molecules are moving but the solid ice molecules are not
D. liquid water molecules can easily move past one another but the
molecules of solid ice cannot
Answer:
D
Explanation:
I just took the final on Biology and got that right.
What Phase is water at 120 degrees Celsius?
what would be the colour of litmus in sodium carbonate?
will make brainliest
Answer:
the color of the litmus paper will turn into blue color because sodium carbonate is basic in nature
In a chemical reaction _________ are the substances present after the reaction?
(PLEASE HELP! I NEED TO GET THIS DONE BY 11:00 PM! SOMEONE TELL ME HOW TO GIVE BRAINILIST BEACAUSE THE PERSON THAT GETS THIS I WILL GIVE BRAINALIST! BUT I DONT KNOW HOW TO SO TELL ME PLEASE! HELPPPPPPPPPPPPPPPP!)
P.S(sorry about the long yelling and again... im in middle school so I am just going to pick chemistry because I don’t know which subject this is, it just says photosynthesis)
Answer:
The substances present after the reaction are called products.
Explanation.
They are called reactants at the start of the reaction.
The atmosphere insulates the planet by trapping in
Bi2(C2O4)5 compound name
Answer:
Bismuth oxalate
Explanation:
In carbon dioxide, London dispersion forces are the only intermolecular forces of
attraction.
a. TRUE
b. FALSE
Answer:
true
Explanation:
CO has two C-O bonds. The dipoles point in opposite directions, so they cancel each other out. Thus, although CO₂ has polar bonds, it is a nonpolar molecule. Therefore, the only intermolecular forces are London dispersion forces.
How have observations in the sky enabled humans to explore and travel?
Answer:
Observations of the sky allowed explorers to mark the passage of time both in hours and through the months of the year. Early astronomers also realized that the night sky does not look the same from different places on the Earth.
Which statement describes the water gas particles in the air above the cup compared with the water liquid
particles in the cup?
The partides move faster and are closer together
The particles move faster and are far apart
The particles move slower and are closer together
The particles move slower and are far apart
Answer:
The particles move faster and are far apart
Explanation:
A substance may exist in three states of matter; solid, liquid and gas.
In the solid state, there is very strong intermolecular forces between the particles of the substance. They can only vibrate or rotate about their mean positions but can not translate.
In the liquid state, the particles of the substance have a greater degree of freedom than in the solid. The magnitude of intermolecular forces is lower than in solids, the molecules can move at low speeds.
In a gas, the molecules are separated from each other with negligible intermolecular interaction hence they move at very high speed.
Therefore, for the water gas particles in the air above the cup; the particles move faster and are far apart.
Convert 48.5 grams of water to moles of water
Answer:
2.70 mol of water.
Explanation:
divide the given mass by the molar mass of water. 48.5 / 18.016g = 2.70 mol water.
what are three uses of oxygen ?
Answer:
Production Of Steel Plastics and textiles
Explanation:
It is many more etc
The solids and liquids with the strongest intermolecular forces of attraction will have the
lowest melting and boiling points.
a. TRUE
b. FALSE
How does the ionosphere help radio transmission?
Explanation:
ionosphere can reflect radio waves directed into the sky back toward the Earth
Both the stomach and the small intestine are involved in the digestion of food.
The churning of food by stomach muscles and peptidase enzymes in the small
intestine both break food molecules into smaller molecules.
Which statement best describes changes to food during digestion?
Answer: I think the answer is The muscle contractions result in physical changes, while the action of the peptidase results in chemical changes.
Explanation: Because the muscles would make the food smaller and the enzymes have a chemical change to it because it changes the molecules in the food.
The chemical processes in food digestion results in the formation of new
substances.
The statement that best describes the changes in food during digestion is;
The churning of the food is a physical process, which results in physical changes while the peptidase results in chemical changes of the food.
Reasons:
The given processes in the digestion of food are;
Stomach: Food churning is the process by which the small intestine vigorously turns ingested food.
Small intestine: The action of the peptidase enzyme is to increase the rate of the digestion of food.
Therefore;
The churning of the food is a physical process, which results in physical changes while the peptidase results in chemical changes of the food.
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The possible question options obtained from a similar question online are;
The churning of the food and peptidase action both results in chemical changes.The churning of the brings about a chemical change, while the peptidase results in a physical change.The churning action brings about physical change, while the peptidase brings about chemical change.Both the churning action and the action of the peptidase result in chemical change. The age of the seafloor __________as you move away from the mid ocean ridges to deep ocean trenches
A decreases
B increases
C does not change
Answer:
stays the same
Explanation:
because the ocean floor usually doesn't spread instead the ocean floor plunges into deep under water canyons called deep ocean trenches.
how many atoms are there in 1g of argon the Avogadro constant is 6.02 x 10^23 per mole relative atomic mass (Ar): AR=40
Answer:
ow many atoms are there in 1g of argon the Avogadro constant is 6.02 x 10^23 per mole relative atomic mass (Ar): AR=40Explanation:
The number of atoms of argon in 1g of argon is 1.5 × 10²² atoms
From the question,
We are to determine the number of atoms present in 1g of argon.
To determine this,
First we will calculate the number of moles of the 1g of argon
From the formula
[tex]Number\ of\ moles = \frac{Mass}{Atomic\ mass}[/tex]
From the given information
Mass of Argon = 1g
Atomic mass of Argon = 40g/mol
∴ Number of moles of Argon = [tex]\frac{1}{40}[/tex]
Number of mole of Argon = 0.025 mole
Now,
For the number of atoms of argon present
Using the formula
Number of atoms = Number of moles × Avogadro's constant
∴ Number of atoms of argon present = 0.025 × 6.022×10²³
Number of atoms of argon present = 1.5055 × 10²² atoms
Number of atoms of argon present ≅ 1.5 × 10²² atoms
Hence, the number of atoms of argon in 1g of argon is 1.5 × 10²² atoms
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Help, and fast! I really need an answer to this.
Answer:
Explanation:says these bars are like co vid i get em right off teh bat