Answer: 40 days
Explanation: The substance completely disintegrates in 20 days the substance completely disintegrates in 40 days 1/8 part of the mass of the substance will be left intact at the end of 40 days.
Which of the following elements has the largest atomic radius (brainliest for right answer)
Aluminum
Silicon
Phosphorus
Sulfer
Chlorine
What is it called when electrons fall back down to their normal energy level and release a photon of light? (Please help I think its called a quantum leap but im not sure!!)
Answer: Photoelectric effect
Explanation:
Elena makes the table below to determine the number of atoms of each element in the chemical formula 3(NH4)2SO4. A table with 3 columns and 4 rows. The first column labeled element has entries nitrogen, hydrogen, sulfur, oxygen. The second column labeled calculation has entries 1 times 2 times 3 , 4 times 2 times 3, 1 times 4 times 3, 4 times 3. The third column labeled total atoms has entries 6, 24, 12, 12. What mistake did Elena make? She should not have multiplied the sulfur atoms by the subscript 4. She should not have multiplied the nitrogen atoms by the subscript 2. She should not have multiplied the oxygen atoms by the coefficient 3. She should not have multiplied the hydrogen atoms by the coefficient 3.
Answer:
c
Explanation:
because i got 100 on the quiz
Answer: A) She should not have multiplied the sulfur atoms by the subscript 4
Explanation: got an 100 on the quiz:)
How many grams of solid lithium hydroxide must be used to prepare 450
mL of 0.55M LiOH solution?
Answer:
Mass = 6.706 g
Explanation:
Given data:
Mass of lithium hydroxide = ?
Volume of lithium hydroxide = 450 mL (450/1000 = 0.450 L)
Molarity of lithium hydroxide = 0.55 M
Solution:
Formula:
Molarity = number of moles / volume in L
0.55 M = number of moles / 0.450 L
Number of moles = 0.55 M × 0.450 L
Number of moles = 0.25 mol
Mass in gram:
Mass = number of moles × molar mass
Mass = 0.25 mol × 23.95 g/mol
Mass = 6.706 g
Which compound is covalently bonded?
Select one:
a. Al2O3 b. Fe2O3 c. SO2 d. CuCl2
Answer:
The answer is D-CuCl2
I hope this helps
Answer:
D.
CuCl2
Explanation:
May it will help you.
An atom has a diameter of 2.00 Å and the nucleus of that atom has a diameter of 7.50×10−5 Å . Determine the fraction of the volume of the atom that is taken up by the nucleus. Assume the atom and the nucleus are a sphere
Answer:
The fraction of the volume of the atom that is taken up by the nucleus is 4.6656\times 10^{-14}4.6656×10
−14
.
The density of a proton is 6.278\times 10^{14} g/cm^36.278×10
14
g/cm
3
.
Explanation:
Diameter of the atom ,d = 2.50 Å
Radius of the atom ,r = 0.5 d=0.5 × 2.50 Å = 1.25Å
Volume of the sphere= \frac{4}{3}\pi r^3
3
4
πr
3
Volume of atom = V
V=\frac{4}{3}\pi r^3V=
3
4
πr
3
..[1]
Diameter of the nucleus ,d' = 9.00\times 10^{-5}\AA9.00×10
−5
A
˚
Radius of the nucleus ,r' = 0.5 d'=0.5\times 9.00\times 10^{-5}\AA=4.5\times 10^{-5}\AA0.5×9.00×10
−5
A
˚
=4.5×10
−5
A
˚
Volume of nucleus = V'
V=\frac{4}{3}\pi r'^3V=
3
4
πr
′3
..[2]
Dividing [2] by [1]
\frac{V'}{V}=\frac{\frac{4}{3}\pi r'^3}{\frac{4}{3}\pi r^3}
V
V
′
=
3
4
πr
3
3
4
πr
′3
=\frac{r'^3}{r^3}=\frac{(4.5\times 10^{-5}\AA)^3}{(1.25 \AA)^3}=
r
3
r
′3
=
(1.25
A
˚
)
3
(4.5×10
−5
A
˚
)
3
\frac{V'}{V}=4.6656\times 10^{-14}
V
V
′
=4.6656×10
−14
The fraction of the volume of the atom that is taken up by the nucleus is 4.6656\times 10^{-14}4.6656×10
−14
.
Diameter of the proton ,d = 1.72\times 10^{-15} m = 1.72\times 10^{-13} cm1.72×10
−15
m=1.72×10
−13
cm
1 m = 100 cm
Radius of the proton,r = 0.5 d=0.5\times 1.72\times 10^{-13} cm=8.6\times 10^{-14} cm0.5×1.72×10
−13
cm=8.6×10
−14
cm
Volume of the sphere= \frac{4}{3}\pi r^3
3
4
πr
3
Volume of atom = V
V=\frac{4}{3}\times 3.14\times (8.6\times 10^{-14} cm)^3=2.664\times 10^{-39}cm^3V=
3
4
×3.14×(8.6×10
−14
cm)
3
=2.664×10
−39
cm
3
Mass of proton, m = 1.0073 amu = 1.0073\times 1.66054\times 10^{-24} g1.0073×1.66054×10
−24
g
1 amu = 1.66054\times 10^{-24} g1amu=1.66054×10
−24
g
Density of the proton : d
d=\frac{m}{V}=\frac{1.0073\times 1.66054\times 10^{-24} g}{2.664\times 10^{-39}cm^3}=6.278\times 10^{14} g/cm^3d=
V
m
=
2.664×10
−39
cm
3
1.0073×1.66054×10
−24
g
=6.278×10
14
g/cm
3
The density of a proton is 6.278\times 10^{14} g/cm^36.278×10
14
g/cm
3
.
Explanation:
set as brainliest
ice _______________ - a collective term for several mechanical weathering processes induced by stresses created by the freezing of water into ice.
Answer: Frost weathering is a collective term for several mechanical weathering processes induced by stresses created by the freezing of water into ice.
FECl3+3NaOH=Fe(OH)3+NaCl
A. Synthesis
B. Decomposition
C. Combustion
D. Single Replacement
E. Double Replacement
Which compound listed below has the largest molar mass?
Ca(OH)2
H20
CaCl2
NH3
Answer: the answer would be CaCI2
Explanation: this was one of my exam questions i got right. :)
When a car takes a sharp turn to the left and the person in the car slides to the right, this
is an example of
A. Newton's First Law of Motion
B. Newton's Second Law of Motion
C. Newton's Third Law of Motion
D. Newton's Law of Gravity
Answer:
It is newtons First Law:)
Explanation:
Why do you think the mass of the egg changed in water and salt water?
Why did it take 2,000 years for scientists to confirm some of Democritus's ideas about?
Answer:
Explanation:
because it took that long for them to think of one.
What were the purposes of this document? Check all that apply. to extend the rights of sovereignty to all states in the Union to declare rights and powers of the United States to mobilize the Louisiana militia for the coming war to dissolve the political bonds between Louisiana and the United States to declare that Louisiana was a free and independent state
Answer:
Sorry that I'm late but the correct answers are to dissolve the political bonds between Louisiana and the united states and to declare that Louisiana was a free and independent state, or D and E
Explanation:
Answer:
The last two
Explanation:
The solubility of potassium chloride is 34 g KCl
100 g H2O
at 20C. What is the maximum amount of KCl that can
dissolve in 200 g of water at 20C?
Answer: When 20 grams of potassium chlorate, KClO3, is dissolved in 100 grams of water at 80 ºC, the solution can be correctly described as:, unsaturated
At approximately what temperature does the solubility of sodium chloride, NaCl, match the solubility of potassium dichromate, K2Cr2O7?, 60 ºC
Explanation:
Two students are given different samples of a substance and are instructed to determine the properties of the substance.
Which statement describes a property that will be the same for both students?
color because it is an extensive property
mass because it is an extensive property
boiling point because it is an intensive property
volume because it is an intensive property
Answer:
C) Boiling point because it is an intensive property.
The statement describes a property that will be the same for both students is (B). mass because it is an extensive property Hence Option (B) is correct.
What is an Extensive Property ?A property known as an extensive property depends on the quantity of materials in a sample. A couple of instances of extensive attributes are mass and volume.
According to how a property varies as the system's size changes, physical qualities of materials and systems are sometimes classified as either intensive or extensive.
Therefore, The statement describes a property that will be the same for both students is (B). mass because it is an extensive property Hence Option (B) is correct.
Learn more about Extensive Property here ;
https://brainly.com/question/12937142
#SPJ6
What is needed for a wind farm to be effective
Answer:
for a effective wind farm you would need wind turbines a windy area a rotation powered generator and something to use it on
Explanation:
I need help with this quickly! thank you ;-;
Answer:
The second choice and can i have brainiest
Explanation:
The presence of dark matter is one piece of evidence that supports the Big Bang theory. Why is this substance called dark matter?
A. The term dark matter describes matter that is so dark in color that it is barely visible with observation instruments such as telescopes.
B. The term dark matter describes the vast areas of the universe where light cannot be seen.
C. The term dark matter describes black holes because they absorb light.
D. The term dark matter describes matter that cannot be seen because it does not give off light. It can only be detected by observing its gravitational effects on other types of matter.
THIS CLASS IS !!!!EARTH SCIENCE!!!!
The substance is called dark matter because the term dark matter describes matter that cannot be seen because it does not give off light. It can only be detected by observing its gravitational effects on other types of matter (option D).
What is dark matter?Dark matter in physics or astronomy are particles of matter that cannot be detected by their radiation but whose presence is inferred from gravitational effects.
According to this question, the presence of dark matter is one piece of evidence that supports the Big Bang theory.
However, this matter is called "dark" because it does not appear to interact with the electromagnetic field i.e. it does not absorb, reflect, or emit electromagnetic radiation and is, therefore, difficult to detect.
Therefore, the substance is called dark matter because the term dark matter describes matter that cannot be seen because it does not give off light. It can only be detected by observing its gravitational effects on other types of matter.
Learn more about dark matter at: https://brainly.com/question/13121227
#SPJ1
8. An elevator is moving upward with a speed of 11 m/s. Three
seconds later, the elevator is still moving upward but its
speed has been reduced to 5 m/s. What is the elevator's
acceleration?
Answer:
Average acceleration = - 2 m/s^2
Explanation: Have a nice day
d.v. hoyt, "an empirical determination of the heating of the earth by the carbon dioxide greenhouse effect", nature 282 (22 november 1979), 388 - 390.
The impact of a higher atmospheric carbon dioxide concentration on Earth's surface temperature has been the subject of numerous theoretical calculations1,2.
Estimates of the rise in Earth's surface temperature brought on by doubling the amount of carbon dioxide in the atmosphere typically fall between 0.7 and 2.9 °C. The temperature rises range from 0.096 to 0.40 °C for a 10% increase in carbon dioxide.All of these conclusions were reached through the use of theoretical models, ranging in complexity from one-dimensional investigations of the planetary radiation budget to three-dimensional general circulation models. Here, a novel solution to this issue is discussed, enabling the calculation of an empirical estimate of the heating of the Earth's surface caused by the greenhouse effect of carbon dioxide.This method suggests that the Earth only warmed by 0.40 °C or less between 1880 and 1970.
Learn more about green house effect here:
https://brainly.com/question/19521661
#SPJ4
Another element, Z, in the same period of the Periodic Table as A, reacts with chlorine to
form a compound with empirical formula ZCl 2. The percentage composition by mass of ZCl 2
is Z, 31.13; Cl , 68.87.
Calculate the relative atomic mass, Ar, of Z.
The relative atomic mass, Ar, of the element Z is 32.1.
What is the relative atomic mass of the element Z?The relative atomic mass of the element Z is determined as follows:
compound formed between Z and Cl is ZCl₂
This implies that Z is an element in group 2A of the periodic table
percentage composition by mass of the elements in ZCl₂ are given as follows: Z = 31.13; Cl = 68.87
atomic mass of Cl = 35.5
mass of Cl in the compound = 35.5 * 2 = 71.0
68.87% of the compound has a mass = 71.0 g
mass of the compound (100%) ZCl₂ = 71.0 * 100/68.87
mass of the compound ZCl₂ = 103.1
Relative atomic mass, Ar, of Z = 103.1 - 71
Relative atomic mass, Ar, of Z = 32.1
Learn more about relative atomic mass at: https://brainly.com/question/23093395
#SPJ1
2. Water is an example of a(n)
a. inorganic b. organic
compound.
d. none of these
c. carbon
it would be A ,inorganic Compound
20 POINTS. What happened to a Gas once thermal energy is removed. What happened to a Gas once Thermal energy is added? Be specific!
When thermal energy is added the gas will become more dense as the atoms come closer together and when thermal energy is added it becomes less dense as the atoms move apart
Chemical ____ are used to represent compounds
Answer:
Its formula :)
Explanation:
hope this helps <3
How would you change the distance between two charged particles to increase the electric force between them by a factor of 25?
Answer:
reduce the distance by the factor of 5
1 Volume of certain amount of a gas at 25°C and
100 cm Hg pressure is 80 mL. The gas is
expanded to 160 mL keeping the temperature
constant. Calculate the pressure of the expanded
Numericals based on Boyle's law
Answer:
P₂ = 50 mmHg
Explanation:
Given data:
Initial volume of gas = 80 mL
Initial pressure of gas = 100 mmHg
Final volume = 160 mL
Final pressure = ?
Temperature = constant
Solution:
The given problem will be solved through the Boyle's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
100 mmHg × 80 mL = P₂ × 160 mL
P₂ = 8000 mmHg. mL/ 160 mL
P₂ = 50 mmHg
Which element would most likely bond with lithium and form an ionic compound?
Answer:
(Please make sure to re-write this on your own to make sure that your teacher doesn't think your cheating!) Fluoride.Explanation:Ionic bonding is the type of bond that is made between a nonmetal and a metal. In this type of union, one of the elements yields electrons and the other accepts electrons.
In this case, the metal is Lithium, we need a nonmetal to complete the union. (Don't know if you need this or anything but here you go)
Beryllium is a metal.
Calcium is a metal.
Fluoride is a nonmetal.
Sodium is a metal.
After the analysis, we conclude that the correct answer is Fluoride since it is the only one that is a nonmetal.
Based on the organization and colors in the periodic table, which two elements do you think are most similar in terms of their properties magnesium (Mg) , barium (Ba) , and gold (Au) ? Explain .
Answer:
Magnesium and barium
Explanation:
They are both Alkaline earth metals. All the alkaline earth metals react with water to produce hydrogen gas and the metal hydroxide, although somewhat less vigorously than the alkali metals.
The organization and colors in the periodic table magnesium and barium are the two element with most of the similar properties because they both belongs to alkaline earth metals.
What are periodic table?
Periodic table are defined as an arrangement of all the elements known to man in accordance with their increasing atomic properties and recurring chemical properties. 118 elements are arranged in periodic table.
Alkaline earth metals are defined as any of the divalent strongly basic metal of group 2 of a periodic table comprising beryllium, magnesium, calcium, barium and radium.
Thus, the organization and colors in the periodic table magnesium and barium are the two element with most of the similar properties because they both belongs to alkaline earth metals.
To learn more about periodic table, refer to the link below:
https://brainly.com/question/11155928
#SPJ5
The electron configuration for Aluminum (Al) is 1s^2 2s^2 2p^6 3s^2 3p^1
How many electrons does aluminum have? and how many of those electrons are valence electrons?
A:11 and 1
B: 11 and 3
C:13 and 1
D:13 and 3
Answer:
Aluminum has 13 electrons with 3 electrons in its valence shell....
Hope it helpss....｡◕‿◕｡
What is the best way to
determine which brand of
paper towel is the
strongest when wet?
Answer:Bounty
Explanation:After being soaked, the Bounty towel held an impressive 43 ounces or 2.69 pounds.
Did this help?