Answer:
Curbing global carbon dioxide emissions has been a challenge, primarily because they are being driven higher by countries with low per capita emissions.
Explanation:
"just trust me bro"
What is the charge of this atom?
65 protons
60 electrons
A)-5
B)+5
C)0
Answer:
B. +5
Explanation:
The melting point of Paradichlorobenzene is 53.0C .In a laboratory activity two students try to verify this value .The first student records 51.5C,53.5C ,55.0C,52.3C and 54.2C.The second student records 52.3C,53.2C,54.0C AND 53.5C. A. Calculate the average value for the two students. B. Calculate the Percent error for each student. C. Which student is most precise ?Most accurate? Explain.
Answer:
a. 53.3°C.
b. Percent error for both students is 53.3°C
c. Both students are equal in accuracy.
2nd student is most precise
Explanation:
The percent error is defined as:
|M - T| / T * 100
Where M is measurement,
and T is theoretical value
a. To obtain the average of both measurements we need to sum the measurements and divide these in the number of measurements:
51.5°C+53.5°C+55.0°C+52.3°C+54.2°C+52.3°C+53.2°C+54.0°C+53.5°C / 9
= 53.3°C
b. Percent error for 1st student:
51.5°C+53.5°C+55.0°C+52.3°C+54.2°C / 5 = 53.3°C
|53.3°C - 53.0°C| / 53°C * 100
0.57%
Percent error for 2nd student:
52.3°C+53.2°C+54.0°C+53.5°C / 4 = 53.3°C
|53.3°C - 53.0°C| / 53°C * 100
0.57%
c. Now, precision is how close are the measurements to each other and the accuracy how close are the measurements to the theoretical value:
The accuracy is obtained with percent error, the lower percent error the most accurate measurement. That means:
both students are equal in accuracy.
And precision is obtained with relative standard desviation.
Desviation standard / Average * 100
(We can solve the standard desviation in a scientific calculator):
1st student:
2.65%
2nd student:
1.34%
The lower RSD the most precise measurements.
2nd student is most preciseCan anyone please help me with this question?? Please
6. Which of the following element pairs would most likely form an ionic compound? (5pts)
a. Ca and Ni b. Cu and Ar c. F and S d. Zn and K e. Na and Cl f. V and O g. He and Xe h. Sn and Na i. C and Br j. Sr and P k. Cr and I l. Ag and NO 3
Answer:
b
Explanation:
Isopentyl acetate is the molecule largely responsible for the aroma and taste of bananas. It is made up of carbon, hydrogen, and oxygen. Combustion of a 3.256-g sample of isopentyl acetate produces 7.706 g CO2 and 3.156 g H2O. Using these results, what is the correct empirical formula for isopentyl acetate?
Answer:
Explanation:
7.706 g of CO₂ will contain 12 x 7.706 / 44 g of C
= 2.1 g of C .
This will be contained in 3.256 g of isopentyl acetate
3.156 g of H₂O will contain 2 x 3.156 / 18 g of H
= .351 g of H
This will be contained in 3.256 g of isopentyl acetate
Rest will be oxygen
amount of oxygen in 3.256 g of isopentyl acetate
= 3.256 - ( 2.1 + .351 )
= .805 g
ratio of C , H , O in isopentyl acetate
= 2.1 g : .351 g : .805 g
2.1 / 12 : .351 / 1 : 0.805 / 16 ratio of moles
= .175 : .351 : .05 ratio of moles
= 3.5 : 7.02: 1
= 7 : 14 : 2
empirical formula of isopentyl acetate
= C₇ H₁₄ O₂ .
help!!!!?????????? plssssssss
Answer: it’s b)
Explanation: that’s the only difference that is listed
Answer:
I think it is B
Explanation:
A year has 365 days, and a day has 24 hours. If an hour has 60 minutes and a minute has 60 seconds, how many seconds are there in 1 year?
54,750 s
525,600 s
3.15 Times. 107 s
1.89 Times. 109 s
Answer:
31,536,000 seconds
Explanation:
off google
Answer:
3.15 x 10^7s
Explanation:
HURRY ITS IS DUE SOON
Answer:
use the meaning of the word see what is similar and what is different about them
carbon + oxygen -->
carbon dioxide
balancing equation
Carbon = C
Oxygen = O
CO2 = Carbondioxide
Balanced equation :
C + O2 = CO2
Answer:
co2
Explanation:
c+o2-------------> co2
The density of water is 1.00 g/mL. Which substance below can float on water?
Answer:
ice, air, ducks and fabric
Explanation:
its common sense
8.
Blank is the transfer of energy by electromagnetic waves.
Your answer
24H2S + 16HNO3 3Sg+ 16NO + 32H2O
Answer:
24 sultur with 48hydrogen+16 hydrogen,nitrogen and 48 oxygen+16 nitrogen,16 oxygen+62hydrogen and 32 oxygen
Explanation:
PLS HELP ME PLS I'LL GIVE BRAINLIEST TO WHOEVER ANSWERS FIRST OR HAS THE BEST ANSWER
Suppose that green spheres represent chlorine atoms, yellow-green spheres represent fluorine atoms, white spheres represent hydrogen atoms, and all the molecules are gases
Answer:
a. Reactants: F₂ and HCl molecules
Products: Cl₂ and HF
b. 4HCl + 2F₂ ----> 4HF + 2Cl₂
c. Single replacement reaction
Note: The question is not complete. The complete question is found below as well as in the attachment.
Suppose that green spheres represent chlorine atoms, yellow-green spheres represent fluorine atoms, white spheres represent hydrogen atoms, and all the molecules are gases:
a. write a formula for each of the reactants
b. write a balanced equation for the reaction
c. indicate the type of reaction as combination,decomposition, single replacement, double replacement, or combustion
Explanation:
a. From the models shown in the diagram, The reactants are F₂, HCl while the products are Cl₂ and HF respectively
b. Equation for the reaction is given below;
4HCl + 2F₂ ----> 4HF + 2Cl₂
c. The reaction is single replacement reaction such that fluorine gas molecules replace the chlorine atoms in hydrogen chloride to form hydrogen fluoride with the liberation of chlorine atoms as gaseous molecules.
An electron moves from an excited state back to the ground state releasing
4.56 x 10-19 J of energy. a) Find the frequency of the photon of light that would be released. b) Find the
wavelength in nm.
Explanation:
The first step in this problem is to convert the wavelength, λ, to a frequency, ν, and
then calculate the energy of the photon using ε = hν. In such problems you must take
care to use a consistent set of units. We will use S.I. units. Thus,
λ = 18900 Å = 18900 x 10–10 m = 1.89 x 10–6 m
The frequency associated with this wavelength is given by:
ν = c/λ = (3.00 x 108 m s–1 ) / (1.89 x 10–6 m) = 1.59 x 1014 s–1
The energy ε associated with a photon of this frequency is:
ε = h ν = (6.626 x 10–34 J s) (1.59 x 1014 s–1) = 1.05 x 10–19 J
Note -- the ENERGY of this photon corresponds to a DIFFERENCE between
energy levels of the H atom
The energy levels for the H atom are given by:
εn = (–21.8 x 10–19 J) / n2 ; where n = 1,2,3,4,.............
Thus, ε1 = –21.8 x 10–19 J; ε2 = –5.45 x 10–19 J
ε3 = –2.42 x 10–19 J; ε4 = –1.36 x 10–19 J
We now seek an ENERGY LEVEL DIFFERENCE which matches the energy of the
photon.
We see that the electronic transition which gives rise to an EMITTED photon with
energy ε = 1.05 x 10–19 J is:
ninitial = 4 → nfinal = 3
2. A series of spectral lines in emission is characterized by a common value of nfinal -- i.e.
the quantum number of the level at which the transition terminates. Since the 18900 Å
line arises from a transition in which ninitial = 4 and nfinal = 3, the series to which it
belongs is characterized by nfinal = 3. The series limit for this series of emission lines is
the wavelength that would correspond to the transition ninitial = ∞ to nfinal = 3
From the energy level expression given in problem1 we see that:
ε∞ = (–21.8 x 10–19 J) (1/ ∞2) = 0
I have the coldest temperature of the atmosphere. Who am I?
Answer:
Jack Frost of course!!!!!!!
what information can you figure out about an atom using only the atomic number?
Help! I am in a hurry! Will get brainliest if correct!
Answer:
nonmetel
Explanation:
Answer:
Its a non-metal
Explanation:
Elements that tend to gain electrons to form anions during chemical reactions are called non-metals. These are electronegative elements. They are non-lustrous, brittle and poor conductors of heat and electricity (except graphite). Non-metals can be gaseous, liquids or solids.
what is the formula for dihydrogen tetraoxide
It's been a while... but I'm pretty sure it's
H₂O₄
What is true about atoms when they bond? There may be more than one answer.
1. Bonded atoms can never be taken apart
2. Electrons can be transferred
3. They form compounds
4. Compounds have the same characteristics are the atoms that make it up
5. Electrons can be shared
Answer:
3. 5. and i think thats it
Answer:
3. 5. and i know it is right
Explanation:
Which type of bond is salt? a. covalent b. valence c. metallic d. ionic
Answer:
D. Ionic
Explanation:
It has ionic bonding! Good luck ^^
How do the data support your claim above? Explain your statement above.
Answer:
the data will support my theory if the results are right for my hypothisis
Answer:
That guys answer is right i'll be trying my best to answer as much wrong in correct answers if wrong i will correct them
Explanation:
sorry i couldn't help theres over more then 200,000 people who uses brainy
HELP ASAPPPP
Cobalt-60 has a half-life of 5.3 years. A sample measures 0.95g of cobalt-
60. If the sample originally had 5.2g of colbalt-60, determine its age in
years or the time elapsed in years. Round up answer in the nearest whole
number and no additional text or unit. *
Answer:
13 years
Explanation:
From;
0.693/t1/2 = 2.303/t log (No/N)
Where;
t1/12 = half-life of Cobalt-60 = 5.3 years
t = time taken = the unknown
No = mass of radioactive material originally present = 5.2 g
N = mass of radioactive material at time t = 0.95 g
Substituting values;
0.693/5.3 = 2.303/t log (5.2/0.95)
0.131 = 2.303/t(0.738)
0.131 = 1.6996/t
t = 1.6996/0.131
t = 12.97 years
t = 13 years(to the nearest whole number)
What is the specific heat of a substance that absorbs 1000 joules of heat when a sample of 25 g of the substance increases in temperature from 10.0C to 60.0C
Answer:
1250000
Explanation:
Specific heat is mass times specific heat capacity times change in temperature to get chance in temperature minus the old temperature from the new temperature then complete equation hence 25g×1000j×(60-10)
25g×1000j×50
=1250000g/j/degree Celsius
who know how to do this thank you
Number of neutrons :
Argon=22
Boron=6
Further explanationThere are two components that accompany an element, the mass number and atomic number
Atoms are composed of 3 types of basic particles (subatomic particles): protons, electrons, and neutrons
The Atomic Number (Z) indicates the number of protons and electrons in an atom of an element.
Atomic number = number of protons = number of electrons ⇒ neutral number
Atomic mass is the sum of protons and neutrons
Atomic Number (Z) = Atomic mass (A) - Number of Neutrons
Argon has an atomic number of 18 and a mass number of 39,948
number of neutrons =
[tex]\tt 39.948-18=21,948\approx 22[/tex]
Boron has an atomic number of 5 and a mass number of 10,811
number of neutrons =
[tex]\tt 10.811-5=5.811\approx 6[/tex]
scientists studying squirrels in a forest observed that the squirrel population decrease over a period of five years. which statement is the most likely explanation for the decrease in the population?
Answer:
1.An increment of predators
2.unavailability of food resources due to change in climate causing famine
3.Spread of diseases over time that might kill the squirrels
4.An increment of squirrels which caused high competition on food,thus some of them had to migrate
5.Might be fire break out over some time that caused death to some squirrels in the reasoning of the period of time
what are green boxes on periodic tables
Answer:
The basic metal ones?
Explanation:
...
Could cellular respiration
happen without photosynthesis? Explain your
reasoning
Answer:
No
Explanation:
Without photosynthesis, there would be no sugar, without which there could be no cellular respiration.Both animal cells and plant cells depend on cellular respiration for their energy needs, because both animal cells and plant cells need ATP.
If a net force of 4 N caused a football to accelerate 8 m/s2 across a football field, what was the mass of the football?
Answer:
Mass is .5kg
Explanation:
F=ma, plug in your numbers:
F=4N
A=8m/s^2
4=m8
m=4/8
Which of the following happens to the particles when the temperature of liquid water drops?
kinetic energy decreases
kinetic energy increases and then decreases
kinetic energy increases
kinetic energy stays constant
Answer:
The Kinetic energy decreases
Explanation:
because the speed of the molecules slows down.
