Answer:
N=9.933×10^23
Explanation:
[tex]n = \frac{m}{mr} [/tex]
N=n×la
Sand is composed of silicon dioxide SiO2. A 210 gram sample has how many moles?
The number of moles of 210 gram sample of sand contains 3.5 moles of mole of SiO₂
Sand is composed of silicon dioxide (SiO₂).
Therefore, let's calculate the molecular mass of SiO₂ . Therefore,
Molecular mass of SiO₂The molecular mass of the compound is the sum of the atomic mass of the compound.
SiO₂ = 32 + (16 × 2) = 28 + 32 = 60 g/molTherefore,
60 g = 1 mole of SiO₂
210 g = ?
cross multiply
number of moles = 210 / 60
number of moles = 21 / 6
number of moles = 3.5 moles
learn more on moles here:https://brainly.com/question/4816100
The diagram represents liquid water in a pan on a hot plate. The liquid water is boiling and changing into water vapor. The process of boiling water is considered to be a
Answer:
Physical change
Explanation:
The molecules are being rearranged as the water changes phases from liquid to gas, but this doesn't change the chemical structure of the water.
What is a function of the backbone in animals?
A. It protects against predators.
B. It regulates blood glucose.
C. It surround the spinal cord.
D. It limits movement.
Which statement is false? a. A closed system does not interact with its surroundings. b. Matter and energy can be transformed in and out of a system c. Energy can be created or destroyed. d. If energy appears to be gained or lost, it has just changed into a different form
Plz help how do I predict the shape of the molecule for GaBr3
Explanation:
GaBr3 is called gallium tribromide. It is composed of one gallium atom and three bromide atoms. Within a molecule of gallium tribormide, there are three bonding electron pairs and zero lone pairs of electrons. Such a configuration results in the trigonal planar molecular shape.
Answer:
GaBr3 is called gallium tribromide.
Explanation:
It is composed of one gallium atom and three bromide atoms. Within a molecule of gallium tribormide, there are three bonding electron pairs and zero lone pairs of electrons. Such a configuration results in the trigonal planar molecular shape.
Hope this helps! :)
What chemical burns red?
Answer:
Strontium chloride
Explanation:
get that W
Answer:
Strontium chloride or strontium nitrate
Explanation:
When KCL dissolved in ethanol, what is the intermolecular attraction between K+ ions and ethanol molecules?
Answer: Ion-Dipole
Explanation: I took the CK-12 practice and got it right
When KCL dissolved in ethanol, the intermolecular attraction between K+ ions and ethanol molecules is ion - dipole interaction.
What is an ion dipole interaction ?The term ion-dipole interaction is defined as the intermolecular force of attraction between cation or anion and a molecule. It is present in the solution where ionic compounds dissolve in polar solvents.
Due to the polar O-H group's presence in the molecule, ethanol is a polar substance. Thus, the molecule has a dipole moment. The dipole's positive end rests on hydrogen, and its negative end rests on oxygen.
K+ ions can interact with the ethanol's negative end of the dipole through ion-dipole interaction when KCl is dissolved in the alcohol.
Thus, When KCL dissolved in ethanol, the intermolecular attraction between K+ ions and ethanol molecules is ion - dipole interaction.
To learn more about an ion dipole interaction, follow the link;
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#SPJ2
Energy in a chemical reaction can be identified as which of the following?
A.) Heat
B.) Light
C.) ∆H
D.) 2,000Kj
E.) All of the above
what are the resulting elements and compounds of a chemical reaction called?
i need the answer in 2 minutes.
Answer:these starting substances of a chemical reaction are called the reactants, and the new substances that result are called the products
Explanation:I hope this helps
What is the percent composition by mass of oxygen in the compound
MgSO4?
20%
46%
53%
27%
particles are very ..........
Answer:
pls comment if this helps
Explanation:
small this is because people cant see them
What cell function produces offspring
Answer:Sexual reproduction produces offspring with novel combinations of genes
Explanation:
yes
80 foot-pounds of work is needed to move the sofa in Tyler's apartment. Which of the following statements is true?
certain conductor with a resistance of 10 Ohms is crossed by an electric current of intensity 100 mA. What is the potential difference at the terminals of that conductor?
Answer:
1.0 V
Explanation:
Step 1: Given data
Resistance of certain conductor (R): 10 ΩCurrent's intensity (I): 100 mAPotential difference at the terminals of that conductor (V): ?Step 2: Convert "I" to Ampere
We will use the conversion factor 1 A = 1000 mA.
100 mA × 1 A/1000 mA = 0.100 A
Step 3: Calculate the potential difference
We will use Ohm's law.
V = I × R
V = 0.100 A × 10 Ω = 1.0 V
4. When is it appropriate to use Roman numerals in naming compounds?
Answer:
Explanation:
Roman numerals are used in naming ionic compounds when the metal cation forms more than one ion.
What is the Molarity of 0.250 L of solution containing 4.32 g of magnesium
phosphide (Mg3P2)?
A. 0.128 M
B. 0.312 M
C. 1.13 M
D. 1.97 M
Pls help I need help with this ..
Answer:
iTS FLIPPED
Explanation:
Answer:
i don't know sorry so lets be friends
If the amount of energy required to break bonds in the reactants is more than the amount of energy released in forming bonds in the products, then the reaction will have a negative change in enthalpy (−ΔH). (2 points)
True
False
CH AT FOR THE WeebsRUs
Answer:
YASSSSSSS
Explanation:
i think the answer is true
I am worried about your proposal to install a groundwater heating system in my daughter’s school.
I don’t think that water at a temperature of 30°C has enough energy to heat the school. If the school is too cold, the students won’t be able to focus on learning.
Respond to David Li’s letter. Explain how the groundwater system could heat the air in the school.
Answer: The temperature would increase assuming it is 30 degree water causing a change in the temperature and assuming it is a seismic groundwater source you are using the earths core to heat the school so it would likely be a stable energy source. There are very few places on the planet where that warm of water is accessible without drilling really deep into the core but if it is there and is a stable fault then the energy would be consistent and stable.
The groundwater system can heat the air in the school by transferring the heat in the ambient atmosphere of school.
Groundwater heating system:
Although the temperature of the ground water is not much but the amount of groundwater is too much.
This large amount water slowly releases heat energy which is transferred in the ambient atmosphere of school.
Therefore, the groundwater system can heat the air in the school by transferring the heat in the ambient atmosphere of school.
To know more about groundwater heating system,
https://brainly.com/question/2029584
I WILL GIVE BRAINLIST!!!!!!!!!!!!!!!!!!!!!! PLZZZZZZZZZ HELPPPPPPPPPPPPPP
Explain how proper motion will affect the constellation as seen from the earth.
Help with stochiometry asap
The sound made by crickets occurs when the male crickets rubs its two hind legs together. Which type of energy transformation results in the sound made by crickets?
A.sound energy to thermal energy
B.thermal energy to chemical energy
C.mechanical energy to sound energy
D.mechanical energy to chemical energy
Answer:
You can simply use process of elimination to find your answer. The only option that results in SOUND energy is C. Therefor your answer would be C.
Explanation:
<3
The rubbing of the hind legs by crickets converts the mechanical energy to sound energy. Thus, option C is correct.
Crickets have been the nocturnal animals that sleep in the daytime and were awake at the night. The crickets have been consisted of the front limbs and hind limbs with a pair of wings that support them to fly.
The crickets make the sound by the rubbing of the legs, thereby creating the vibrational sounds that have been sound energy.
The rubbing of legs has been utilized as the mechanical energy or the energy of doing work. The mechanical energy has been converted to the vibrational energy that contributes to the energy of the sound waves, thereby the sound energy.
Thus, the rubbing of the hind legs by crickets converts the mechanical energy to sound energy. Thus, option C is correct.
For more information about the energy transformation, refer to the link:
https://brainly.com/question/10555430
Nitrogen (N) and hydrogen (H) react with each other to produce ammonia (NH3). This reaction is shown in an equation as N2 + 3H2 → 2NH3. What is the ratio of nitrogen atoms to hydrogen atoms in ammonia?
Answer:
the ratio is 1:3
Explanation:
you must find it
please answer 3 plzzzz
7th grade science
Answer:
Explanation:
Show us the picture, then we can help.
H2SO3
What does this stand for?
Answer:
It means Sulfurous Acid
Explanation:
The Milky Way Galaxy is made up of billions of stars. Which of the following best describes the shape of the Milky Way Galaxy
OA. a sphere
OB. a pyramid
C a spiral
OD
a cube
Answer:
It's spiral for any of my study island people.
Explanation:
classify the reaction
Answer:
Synthesis reaction
Explanation:
2Hg+O2 ⇒ 2HgO is in the direction of off
Element + Other Element ⇒ Product
The conceptual model of a synthesis reaction is 2Hg+O2 ⇒ 2HgO
can you help me with this i don't think it is that hard i just have a lot on my mind.
Answer:
Global wind
Explanation:
The jet streams go around the whole earth from west to east
Hope you have a good day :)
How many primary consumers are pictured in the food web? 1 2 3 4
Answer:2
Explanation:
What kind of bond will form when Sodium and Nitrogen react?
Answer: Ionic Bonds
"When it forms the nitride ion, it gains three electrons to form a 3- ion: N3− . In ionic compounds, the charges of constituent ions must balance. This can be achieved by having three sodium ions per nitride ion. Therefore, the formula of sodium nitride is Na3N"
Explanation:
https://socratic.org/questions/what-is-the-formula-for-sodium-nitride#:~:text=When%20it%20forms%20the%20nitride,nitride%20is%20Na3N%20.