Answer:
From this solution, you can do the a number question answer.
Why Should a magnesium ribbon be cleaned before burning ?
A magnesium ribbon is cleaned to remove the protective layer of basic magnesium carbonate from its surface, so that it may readily combine with the oxygen in air (on heating).
Answer:
Magnesium gets covered with a layer of magnesium oxide when kept in air for a long time. This layer hinders the burning of magnesium. Hence, it is to be cleaned before burning.
Calculate the average atomic mass for element X.
(Please HELP)
A balloon, inflated in an air-conditioned room at 27.0°C, has a volume
of 4.50.L. It is heated to a temperature of 57.0°C. What is the new
volume of the balloon if the pressure remains constant?
Answer:
4.95L
Explanation:
Using Charle's law equation;
V1/T1 = V2/T2
Where;
V1 = initial volume (L)
V2 = final volume (L)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the question, the following information was given:
V1 = 4.50L
V2 = ?
T1 = 27°C = 27 + 273 = 300K
T2 = 57°C = 57 + 273 = 330K
Using V1/T1 = V2/T2
4.50/300 = V2/330
Cross multiply
300 × V2 = 4.5 × 330
300V2 = 1485
V2 = 1485 ÷ 300
V2 = 4.95L
PLEASE HELP
Which of the following correctly orders the types of radiation from the LONGEST wavelength to the SHORTEST wavelength?
A. Green Visible Light, Red Visible Light, Blue Visible Light, Ultraviolet
B. Microwave, Orange Visible Light, Ultraviolet, Violet Visible Light
C. Red Visible Light, Infrared, Microwaves, Radio waves
D. Microwave, Blue Visible Light, Ultraviolet, Gamma
Answer:
D. Microwave, Blue Visible Light, Ultraviolet, Gamma
Explanation:
colors longest to shortest are
red green blue violet
longest wavelength to shortest:
radio waves, microwaves, infrared, optical, ultraviolet, X-rays, and gamma-rays.
Methane is approximately 23 times more powerful than carbon dioxide as a greenhouse gas. Which are significant sources of methane emissions
Answer:
anthropogenic sources like landfills, agricultural activities,coal mining and combustion and some sources are natural ones
Metals like potassium and sodium are kept in paroffin oil. Why?
Answer:
because they are high reactive to the air thats why we keep them in paroffin oil
Find the mass in grams of 15.00 moles of AICI:
Answer:
937.5g
Explanation:
No of moles = mass ÷ molar mass
According to this question, there are 15moles of the compound; AlCl
Molar mass of AlCl = 27 + 35.5
= 62.5g/mol
Using n = m/M.M
15 = m/62.5
m = 15 × 62.5
m = 937.5g
The most common carrier of communicable diseases are
a.cockroach
b.housefly
c.mosquito
d.spider
housefly
Explanation:
Because it one of the affective vector of disease carrier and it always roam towards wastes and dirty materials likely to get attracted . And it carries contagious disease from hospitals , infected patients , etc .
The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction _____.
describe the formation of ionic bonds in potassium chloride compound (5 marks)
Answer:
When the two atoms are in contact, potassium readily transfers its outer electron to chlorine which readily accepts it, resulting in both atoms achieving a state of eight outermost electrons. With this electron transfer, the ionic bond in KCl is formed.
How are carbon-based molecules suited for sustaining life?
[tex]\huge\fcolorbox{red}{pink}{Answer ♥}[/tex]
Life on Earth is based on carbon, likely because each carbon atom can form bonds with up to four other atoms simultaneously. This quality makes carbon well-suited to form the long chains of molecules that serve as the basis for life as we know it, such as proteins and DNA.
Hope it helps uh ✌️✌️✌️
How many molecular of H2O and O2 are present in 8.5g of H2O2 ?
2H2O+O2--->2H2O2
8.5 gm H2O2=0.25 mole
hence H2O is also 0.25 mole i.e.4.5 gm
O2is 0.125 mole i.e.4 gm
Diego is trying to lift a piano to the second floor of his house. Diego uses a pulley system and gives a big lift to the piano.The piano moves upward, then stops, and then it starts to fall to the ground. (The direction of the force of gravity is negative.) Which list best describes the forces on the piano in the proper order
Answer:
positive force → balanced force → negative force
Explanation:
np
Answer:
positive force → balanced force → negative force
Explanation:
:)))
different oil refineries in UAE
Answer:
Petroleum refinery capacity in the UAE 2009-2018
In 2018, the total production capacities of all refineries in the UAE were 1.13 metric barrels per day. Total total production capacity of the al-Ruwais refinery in the United Arab Emirates was approximately 817,000 metric barrels per day.
HELP ASAP Choose three sections of the electromagnetic spectrum. Rank them in order of energy. Give an example of how they are used for each.
5.34x10 to the 27th power molecules of sulfur hexafluoride to moles of sulfur hexafluoride
Answer:
8.87 × 10³ moles.
Explanation:
To convert number of molecules of sulfur hexafluoride (SF6) to moles (n), we divide by Avogadro's number (6.02 × 10²³)
That is; n = N ÷ nA
According to the question, 5.34 x 10^27 molecules of SF6 was given in this question. Hence, the number of moles it contains is given as:
n = 5.34 x 10^27 ÷ 6.02 × 10²³
n = 5.34/6.02 × 10^ (27-23)
n = 0.887 × 10⁴
n = 8.87 × 10³ moles.
Why is the charge on a charged sphere distributed uniformly over its surface?
-Similar charges seek to be the minimum distance possible from each other.
-Opposite charges seek to be the maximum distance possible from each other.
-Similar charges seek to be the maximum distance possible from each other.
-None of the above
Answer:
Similar charges seek to be the maximum distance possible from each other
Explanation:
On a charged sphere, there are like charges and these like charges are repelled by each other to the far ends of the sphere. Hence they are distributed uniformly in the sphere.
How does the alcohol enter the body? Describe the process. Where does most of the absorption take place?
Explanation: Once swallowed, a drink enters the stomach and small intestine, where small blood vessels carry it to the bloodstream. Approximately 20% of alcohol is absorbed through the stomach and most of the remaining 80% is absorbed through the small intestine.
An atom has9 electrons and 9 protons at the start. If it loses 2 electrons, what would the net charge on the atom be
Answer:
i hope it will help you
Explanation:
there will be 7 electrons and 9 protons will have 2+ charge.
if sneezing is the response to smelling food is it conditioned or unconditioned
Answer:
i think its unconditioned response.hope it helpsstay safe healthy and happy.Which statement is the best description of a chemical bond
Answer:
What are your given options? I can't answer unless I know those :)
Explanation:
convert 300g into kg
Answer:
0.3kg
Explanation:
1. Which of the following species exhibit tetrahedral geometry?
a. CCl4 b. PCI5 c. NH3 d. CO2
2. Which statement correctly describes the Valence Shell Electron Pair Repulsion (VSEPR) Theory? The valence electron pairs are__________.
a. The valence electron pairs are given by the group number in the periodic table.
b. The valence electron pairs are the outermost electrons of the atom that areinvolved in the bonding.
c. The valence electron pairs repel one another and tend to stay as far apart aspossible.
d. The valence electron pairs are the lone pairs of the atom.
3. Which of the following statements about resonance is TRUE?
I. Resonance hybrids occur because a compound changes back and forth between two or more resonancestructures
II. Resonance structures differ in the arrangement of electrons but not in the arrangement of atoms.
III. Resonance hybrids contain delocalized electrons.
IV. Resonance structures for a given compound always contribute equally to the resonance hybrid.
V. Resonance structures occur when there are two or more valid Lewis structures for a given compound.
VI. Resonance hybrids are a composite of resonance structures.
a.I, II, V, VI
b. II, III, IV, VI
c. II, III, V, VI
d. II, IV, V, VI
4. How many resonance forms will nitrate ion (NO3) have?
a. - 1 b. 1 c. 2 d. 3
5. What is the first noble gas?
a. Xenon b. Radon c. Helium d. Krypton
6. What is the principle used for filling of atomic orbitals?
a. Azimithual Principle
b. Hund's Principle
c. Pauling's Exclusion Principle
d. Aufbau Principle
7. How many electrons can "m" shell accommodate?
a. 16 b. 17 c. 18 d. 19
8. What number of shells used for the accommodation of electrons in an atom? a. one b. two c. three d. four
9. What distribution does the electron configuration describe?
a. protons
b. neutrons
c. electrons
d. ions
10. How many total electrons can the "p" orbitals hold?
a. 3 b. 1 c. 7 d. 6
11. Who are the founding fathers of Quantum Mechanics?
a. Werner Karl Heisenberg
b. Isaac Newton
c. Erwin Schrodinger
d. a and c
12. There are _types of quantum numbers.
a. 2 b. 4 c. 5 d. 7
13. Which of the following elements can only form one bond in a Lewis structure? a. H b. O c. Al d. N
14. Which rule states that electron will go into empty orbitals of the same energy before entering into an orbital with an electron present?
a. Hand's rule
b. Hund's rule
c. Pauli Exclusion Principle
d. Aufbau Principle
15. What is the definition of diamagnetic atom?
a. An atom where all of the electrons are paired
b. An atom where some of the electrons are paired.
c. An atom where none of the electrons are paired.
d. An atom attracted to a magnetic field.
Answer:
a
Explanation:
Its because ammonium has thee hydrogen atoms
I’ll mark you as brainlister
How many moles of carbon are in the sample?
Answer:
12.01 grams per mole
Explanation:
theres no sample or example so if theres grams of Carbon, convert it to moles using 12.01g/mol
In an electrically neutral atom, the number of
protons equals the number of neutrons.
protons equals the number of electrons.
neutrons equals the number of electrons.
A. Protons equals the number of neutrons
B. Protons equal the number of electrons
C. Neutrons equals the number of electrons
Answer: B
Answer:
B
Explanation:
because protons have a +1 charge and electrons have a -1 charge, so if an atom is neutral it must have the same amount of protons and neutrons
which states of matter can flow from one place to another
Answer:
Liquid
Explanation:
Quite an easy question!
Answer:
Liquid
Explanation:
I was passing by lol
in heating a kettle of water on an electric stove, 3.34×10^3 J of thermal energy was provided by the element of the stove. yet, the water in the kettle gained only 5.95×10^2 J of thermal energy. determine the percent efficiency of the electrical element in heating the kettle of water
Answer:
The percentage efficiency of the electrical element is approximately 82.186%
Explanation:
The given parameters are;
The thermal energy provided by the stove element, [tex]H_{supplied}[/tex] = 3.34 × 10³ J
The amount thermal energy gained by the kettle, [tex]H_{absorbed}[/tex] = 5.95 × 10² J
The percentage efficiency of the electrical element in heating the kettle of water, η%, is given as follows;
[tex]\eta \% = \dfrac{H_{supplied} - H_{absorbed} }{H_{supplied}} \times 100[/tex]
Therefore, we get;
[tex]\eta \% = \dfrac{3.34 \times 10^3 - 5.95 \times 10^2}{3.34 \times 10^3} \times 100 = \dfrac{549}{668} \times 100 \approx 82.186 \%[/tex]
The percentage efficiency of the electrical element, η% ≈ 82.186%.
Someone please do a True or false of all of these
Answer:
1. False
2. True
3. False
4. False
5. True
6. False
7. True
8. True
9. True
please help. need this asap!!
Answer:
E.....Na2I.,.
Explanation:
Cuz sodium has a Vallency..1......lodide has Vallency 2