Answer:
Mostly, the molecule has a planar geometry allows free rotation of bonds. The chemical structure of the compound could be given as below. Urea Formula Molecular Mass. This molecule is generally available in final products of proteins of metabolism of humans and animals. Its main existence can be felt in the urine of humans that is formed
Explanation:
the molecular formula of urea is CH4ON2 if the %by mass of 02 atoms is one mole of urea molecule is 26.66%
If a radioactive source has a half life of 2 hours how long will it take for the activity to go from 200 to 25?
Answer:
It takes 6h to the radioactive source decrease its activity from 200 to 25
Explanation:
The equation that describes the readioactive decay is:
Ln [A] = -kt + Ln [A]₀
Where [A] could be taken as activity of the source after time t, [A]₀ is initial activity and k is decay constant.
Decay constant could be written as:
k = ln2 / Half-life
k = ln 2 / 2h
k = 0.3466h⁻¹
Replacing in decay equation:
Ln [25] = -0.3466h⁻¹t + Ln [200]
-2.0794 = -0.3466h⁻¹t
6h = t
It takes 6h to the radioactive source decrease its activity from 200 to 25
What are two properties that make a metal a good choice to use a wire in electronics? *
Answer:
Explanation:
The two properties that make a metal a good choice to use a wire in electronics are :
ductility conductivityAmmonia (NH3) reacts with oxygen (O2) to produce water and nitric oxide (NO). How many grams of water are produced when 22.5 grams of oxygen are reacted?
Explain why hydrocarbons are present in so many different compounds.
Answer:
Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil.
Based on the table above, which amount of a compound dissolved in 100 grams of water at the stated temperature represents a system at equilibrium?
Select one:
a. 40 g NaCl at 70 degrees Celsius
b. 20 g KClO3 at 70 degrees Celsius
c. 80 g NaNO3at 10 degrees Celsius
d. 80 g Pb(NO3)2 at 30 degrees Celsius
Answer:
C. 80g Nano3 at 10 degrees Celsius
Explanation:
I just took the test
80 g NaNO₃ at 10 degrees Celsius of a compound dissolved in 100 grams of water at the stated temperature represents a system at equilibrium. Therefore, option C is correct.
What is solubility ?The maximum quantity of a chemical that will dissolve in a given amount of solvent at a particular temperature is referred to as its solubility.
Different compounds have very varying solubilities, which is a feature of a particular solute-solvent pair.
A substance's physical and chemical characteristics affect how soluble it is. A few other factors and circumstances can also influence it. A few of these are: temperature, pressure, kind of binding, and forces between the particles.
A system is said to be in equilibrium when 80 grammes of a substance, dissolved in 100 grams of water at 10 degrees Celsius.
Thus, option C is correct.
To learn more about the solubility, follow the link;
https://brainly.com/question/28170449
#SPJ2
what is an acid containg oxygen?
Explanation:
An oxyacid, oxoacid, or ternary acid is an acid that contains oxygen. Specifically, it is a compound that contains hydrogen, oxygen, and at least one other element, with at least one hydrogen atom bonded to oxygen that can dissociate to produce the H+ cation and the anion of the acid.
Answer:
oxyacid, oxoacid
Explanation:
An oxyacid, oxoacid, or ternary acid is an acid that contains oxygen. Specifically, it is a compound that contains hydrogen, oxygen, and at least one other element, with at least one hydrogen atom bonded to oxygen that can dissociate to produce the H+ cation and the anion of the acid.
Thomas sits half way down a grassy slope. What force stopped him slamming down
Balance Na + SO3 = Na2SO3
A typical tincture of iodine contains about 2.0% iodine by mass. Calculate
the mass of iodine in a 500. g tincture.
Explain why is ortho nitrophenol more acidic than ortho methoxyphenol
Answer:
Ortho nitrophenol is more acidic than ortho-methoxyphenol.
Reason:
This is because the nitro-group is an electron-withdrawing group. In the case of ortho methoxyphenol; methoxy group is an electron-releasing group. Thus, it increases the electron density in the O−H bond and hence, the proton cannot be given out easily.
Hope this helps you. Do mark me as brainliest.
Why are poisons used less today than they were in the past? What factors influenced this change.
Answer:
Poisons are used less today than they were in the past because forensic scientists can easily detect many substances and toxins during an autopsy.
The main factor that influenced this change is advancements in forensic toxicology knowledge and technology.
good luck, i hope this helps :)
Explanation:
Today poisons are used less because forensic scientists now have much more equipment and have an easier time at identifying poisons like arsenic, which were not so easy to find in the past. The main factor influencing this change is the new technology and knowledge that was unavailable in the past.
When kci dissolved in ethanol what is the intermolecular attraction between k+ ions and ethanol molecules
Answer:
ion-dipole interaction
Explanation:
Ethanol is a polar molecule due to the presence of the polar O-H group in the molecule. This means that the molecule has a dipole moment.
The positive end of the dipole lies on hydrogen while the negative end of the dipole lies on oxygen.
When KCl is dissolved in ethanol, K^+ ions can interact with the negative end of the dipole in ethanol by ion-dipole interaction.
Some seawater is evaporated. The sea salt obtained is found
to be 86% sodium chloride. How much sodium chloride
could be obtained from 200 g of this salt?
Answer:
the answer is 172g
Explanation:
200 × 0.86 = 172g
Question 19 Multiple Choice Worth 3 points)
(06.04 MC)
What forensic scientist established the 'Body Farm' to study the ways bodies decompose under different circumstances?
Matheiu Orfila
Sir Edward Henry
Phillipe Locard
Bill Bass
Answer:
The answer is D Bill Bass
Explanation:
Remember it from the lesson and I took the test.
What is the molecular formula for C5H7 if its molar mass is 536 g/mol?
Answer:
(C5H7)8
Explanation:
It's empirical formula is given as; C5H7
Molar mass of carbon(C) = 12 g/mol
Molar mass of hydrogen(H) = 1 g/mol
We are told that it's molar mass is 536 g/mol.
To find the molecular formula;
Molecular formula = n × empirical formula
Thus;
n = 536/((12 × 5) + (1 × 7))
n = 8
Thus;
Molecular formula = (C5H7)8
What is the SI unit of time?
A.
second
B.
minute
C.
hour
D. day
Answer:
option a. second
.............
Which type of plate boundary is associated with seafloor spreading at the source of the spread: convergent, divergent, or transform?
Answer:
The answer is divergent
How many grams are in 0.75 moles of Fe
Answer:
41.88375 g Fe
Explanation:
Using stoichiometry, we can do this problem. First, we put our given. Then we create an equation using the molar mass of Fe (found on the periodic table, which was 55.845 g Fe), and the resulting equation is:
[tex]0.75 mol Fe * \frac{55.845 g Fe}{1 mol Fe}[/tex]
The mol Fe's cancel, and leave us with:
41.88375 g Fe
Good luck.
Oddly shaped bones like your vertebrae and pelvis? a.irregular bones c. short bones b. flat bones d. long bones
Plants cannot grow too close together because their Blank______ need to spread out and absorb nutrients from the soil.
their roots need room to spread out
how many molecules are in SO4
Answer:
there are 5 molecules in SO⁴
In order to produce CO2, a student put a sample of calcium carbonate in a flask and added hydrochloric acid using the following equation: Ca(CO3) + HCl → H2O + CO2 + CaCl2 The student finds the mass of CO2 generated to be 100 g. If the student began with 200 g of HCl and there was ample CaCO3 left unreacted, what was the percent yield?
Answer:
82.9% Is the percent yield
Explanation:
First, we need to balance the equation.
Ca(CO3) + 2HCl → H2O + CO2 + CaCl2
Since the problem tells you that the excess reactant is Ca(CO3), we just need to Stoichiometry to solve for the theoretical yield.
[tex]\frac{200g HCl}{1}[/tex] x [tex]\frac{1 mole HCl}{36.46gHCl}[/tex] x [tex]\frac{1 mol CO2}{2molHCl}[/tex] x [tex]\frac{44.01CO2}{1molCO2}[/tex] =120.707 g (theoretical yield)
Take your actual yield of 100g, divide that by 120.707, then multiply that decimical by 100.
How many atoms of cobalt are in 4 moles of cobalt?
2 × 10²⁴ atoms Co
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
4 mol Co (Cobalt)
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: [tex]\displaystyle 4 \ mol \ Co(\frac{6.022 \cdot 10^{23} \ atoms \ Co}{1 \ mol \ Co})[/tex]Multiply/Divide: [tex]\displaystyle 2.4088 \cdot 10^{24} \ atoms \ Co[/tex]Step 4: Check
Follow sig fig rules and round. We are given 1 sig fig.
2.4088 × 10²⁴ atoms Co ≈ 2 × 10²⁴ atoms Co
What season is it in earths northern hemisphere when earths northern hemisphere tilts toward the sun
Answer:
Summer
Explanation:
Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive the Sun's most direct rays. So, when the North Pole tilts toward the Sun, it's summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, it's winter in the Northern Hemisphere.
Hope it helped!! Please mark as Brainliest!
Answer:
Summer took the test and got it right
Explanation:
Which season will the northern hemisphere experience when the axis of Earth is tilted towards the sun?
Summer
Which characteristic is true of sexual reproduction but not of asexual reproduction?
Answer:
j one or more parents. that's the answer
What do plants need in order to make food?
A. water, energy, oxygen
B.carbon dioxide, energy, oxygen
C.water, energy, carbon dioxide
D.water, oxygen, carbon dioxide
Answer:
Water, solar energy, carbon dioxide
Explanation:
This image models…
diffraction
reflection
refraction
absorption
Answer:
reflection is correct answer by my views
How many atoms of oxygen are in a molecule
of
glucose (C6H1206)?
Be sure to use the correct place value.
Answer:
Um... 6
Explanation:
C6H12O6
The O is oxygen and the 6 is the exact number of atoms
A cup of coffee is made in the morning by pouring water ov er ground up coffee beans in a piece of paper and by collecting the brown liquid that comes through. Which techniques used
Answer: Filtration technique
Explanation:
The technique used here is called filtration.
Filtration,is a physical separation process that separates a mixture of an insoluble solid from a liquid ( acting as the solvent) by the use of a filter barrier that allows only the fluid to pass through.
In the case from the question,
As water is poured over the ground coffee, it forms a mixture of which the insoluble solid is the coffee grounds, the water is the liquid and the filter barrier is the piece of paper which allows only the brown liquid coffee to pass through as the filtrate.
anyone know this? i’m having trouble...please help.