Answer:
02 ;D h2oooooooooooo
long story shortB
Explanation:
Answer:
B
Explanation:
2H2→Hydrogen peroxide
O2→oxygen
"A water molecule (formally known as dihydrogen monoxide) is composed of two hydrogen atoms and one oxygen atom. ... The actual reaction to make water is a bit more complicated: 2H2 + O2 = 2H2O + Energy"
"A reactant is a substance that is present at the start of a chemical reaction. The substance(s) to the right of the arrow are called products . A product is a substance that is present at the end of a chemical reaction."
The answer is B, hope this helps :)
Describe how the composition of the upper mantle is different from the lower mantle?
a. The upper mantle is made of solid rocks and lower mantle is made of melted rocks and minerals
b. The upper mantle is made of melted rocks and minerals and lower mantle is made of solid rocks
c.The upper mantle is made of lava and the lower mantle is made of magma
Answer:
b
Explanation:
Answer:
it is B hope I helped
=
Explanation:
During ____, the chromatin condenses to make ____.
prophase, chromosomes
metaphase, chromosomes
prophase, DNA
metaphase, DNA
Summarize the history of radioactivity by choosing the scientist(s) involved with each discovery.
conducted experiments with uranium-containing minerals and pure uranium.
came up with the term “radioactivity.”
showed that uranium in a mineral gave off radiation even without being exposed to the Sun.
discovered radium and polonium.
conducted experiments with fluorescent minerals and photographic plates.
Answer:
Marie and Pierre CurieMarie and Pierre CurieAntoine Henri BecquerelMarie and Pierre CurieAntoine Henri BecquerelExplanation: Correct on Edg 2020/2021.
Calcium
and what
makes bones hard
How many moles of nitrogen are in a 14.57 gram sample of nitrogen?
Answer:
[tex]\boxed {\boxed {\sf About \ 1.040 \ moles \ of \ nitrogen }}[/tex]
Explanation:
To convert from grams to moles, we must use the molar mass. This can be found on the Periodic Table. We have a sample of nitrogen, so look for N on the table.
Nitrogen (N): 14.007 g/molNow, use this molar mass as a ratio.
[tex]\frac {14.007 \ g \ N }{1 \ mol \ N }[/tex]
Multiply by the number of grams in the sample (14.57)
[tex]14.57 \ g \ N *\frac {14.007 \ g \ N }{1 \ mol \ N }[/tex]
Flip the fraction so the grams of nitrogen will cancel.
[tex]14.57 \ g \ N *\frac {1 \ mol \ N }{14.007 \ g \ N}[/tex]
[tex]14.57 *\frac {1 \ mol \ N }{14.007 }[/tex]
[tex]\frac {14.57 \ mol \ N }{14.007 }[/tex]
[tex]1.04019419 \ mol \ N \\[/tex]
The original measurement of grams had 4 significant figures, so we need to round our answer to the same number of sig figs.
For the number we calculated, that is the thousandth place. The 1 in the ten thousandth place tells us to keep the 0 in the thousandth place.
[tex]1.040 \ mol \ N[/tex]
There are about 1.040 moles of nitrogen in 14.57 grams.
Most of the carbon in the rocks that form Earth's mantle and crust was stored there when Earth formed. The rest of Earth's carbon is stored and exchanged in many ways.In a model of the carbon cycle, which process does NOT contribute directly to the storage of carbon within sediment?
Answer:
Photosynthesis.
Explanation:
In photosynthesis process, carbondioxide gas enters into plant leaves from which plant produces organic molecules such as glucose. This glucose helps the plant to increase it growth and complete development stages and finally the plant dies and buried in the soil so due to decomposition process, the carbon present in the plant body releases in the soil and become part of sediments. So indirectly photosynthesis process provides carbon to the soil.
what is the molecular formula of benzoyl peroxide (c7h5o2) of the molecular mass is 0.242 kg/mol?(show work please)
Answer : The molecular formula of benzoyl peroxide is [tex]C_{14}H_{10}O_4[/tex]
Explanation :
Empirical formula : It is the simplest form of the chemical formula which depicts the whole number of atoms of each element present in the compound.
Molecular formula : it is the chemical formula which depicts the actual number of atoms of each element present in the compound.
For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.
The equation used to calculate the valency is :
[tex]n=\frac{\text{Molecular mass}}{\text{Empirical mass}}[/tex]
As we are given that the molar mass of compound is, 0.242 kg/mol.
Molecular mass = 0.242 kg/mol = 242 g/mol (1 kg = 1000 g)
The empirical mass of [tex]C_7H_5O_2[/tex] = 7(12) + 5(1) + 2(16) = 121 g/eq
[tex]n=\frac{\text{Molecular mass}}{\text{Empirical mass}}[/tex]
[tex]n=\frac{242}{121}[/tex]
[tex]n=2[/tex]
Molecular formula = [tex](C_7H_5O_2)_n[/tex] = [tex](C_7H_5O_2)_2[/tex] = [tex]C_{14}H_{10}O_4[/tex]
Thus, the molecular formula of benzoyl peroxide is [tex]C_{14}H_{10}O_4[/tex]
A scientist has 207.45g of H2O in a beaker. How many water molecules are in the beaker?
Answer:
6.94 x 10²⁴molecules
Explanation:
Given parameters:
Mass of water = 207.45g
Unknown:
Number of molecules = ?
Solution:
To solve this problem, we must understand:
1 mole of a substance contains 6.02 x 10²³ molecules
Now, first find the number of moles of water;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of water = 2(1) + 16 = 18g/mol
Number of moles = [tex]\frac{207.45}{18}[/tex] = 11.53moles
So;
1 mole of a substance contains 6.02 x 10²³ molecules
11.53moles of carbon dioxide will contain 11.53 x 6.02 x 10²³
= 6.94 x 10²⁴molecules
1. What is the basic unit of structure and function in a living thing
called?
2. How did the invention of the microscope help scientists learn
more about living things?
3. Who was the first to discover cells?
4. Draw a timeline that shows the dates, discoveries, and
scientists involved in the development of the cell theory.
5. What are the four statements of the cell theory?
6. What are specialized cells? List three examples.
7. What are four similarities that all cells share?
8. List the cell part for each letter on the diagram below. What is
the function of each part?
What does the nucleus of an atom do to its own electrons? To the electrons of a nearby atom?
A doctor's order is 0.500 g of ampicillin. The liquid suspension on hand contains 250 mg/5.0 mL. How many milliliters of the suspension are required?
The volume of the suspension required : 10 ml
Further explanationGiven
0.500 g of ampicillin
The liquid suspension concentration = 250 mg/5 mL
Required
The volume of the suspension required
Solution
The concentration of a substance can be expressed in various units such as molarity, ppm, g / L etc.
Each unit change, we must pay attention to the conversion factor
Conversion g to mg
0.5 g = 500 mg
The volume of the suspension needed :
=mass x concentration
[tex]\tt \dfrac{500~mg}{250~mg/5~ml}=500~mg\times \dfrac{5~ml}{250~mg}\\\\=10~ml[/tex]
A science teacher gave a student a sample of a clear liquid labeled "unknown
substance." Which property would best help the student determine the
sample's identity?
A. The sample's boiling point
B. The sample's mass
C. The sample's volume
D. The sample's weight
Answer:
A. The sample's boiling point
Explanation:
Because by knowing boiling point we easily find a substance for example if given clear liquid boiling point is 100 c° we immediately know this is water.
Moreover boiling point is a fixed quantity for a substance.
Which material has been recycled for over 3,000 years?
Answer:
plastic
Explanation:
Write a complete balanced equation for the following reaction:
magnesium metal reacts with oxygen gas
Explanation:
Given species:
Magnesium metals = Mg
Oxygen gas = O₂
Magnesium metal and oxygen gas are the reactants in this chemical process,
2Mg + O₂ → 2MgO
The product of the reaction is MgO because both oxygen and magnesium are divalent.
This reaction is called a combination reaction where two species combines to form a single compound.
Carbon Monoxide is a toxic gas that is colorless and tasteless. How many moles of CO are in 1 L of the gas at STP?
28 moles
0.045 moles
22.4 moles
0.224 moles
Answer:
0.045 moles
Explanation:
Given data:
Moles of CO = ?
Volume of gas = 1 L
Temperature and pressure = standard
Solution:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
n = PV/RT
n = 1 atm× 1L / 0.0821 atm.L/mol.K × 273 K
n = 1 atm.L / 22.41 atm.L/mol
n = 0.045 mol
When shark pups are small what do they eat
Answer:
The baby sharks are not connected to their mum through an umbilical cord. Instead, they feed on their egg's yolk supply, other unfertilized eggs or even the embryos of their brothers and sisters. Through the latter method, only the strongest 1-3 sharks will get born, which is seen in the sand tiger shark.
Explanation:
Write the chief ore of sodium and potassium respectively?
Answer:
K-sylvite
Na-rock salt
Explanation:
Sylvite is a colourless or white mineral consisting of potassium chloride, occurring typically as cubic crystals(Oxford dictionary). It is the primary ore of potassium metal. It appears colorless, sometimes with a shade of red.
Rock salt is a primary ore of sodium. It is found in rocks, seas etc. Rock salt is sometimes commonly called halite. It usually appears white in colour and is rich in sodium.
The burning of a sample of propane generated 1 04.6 kJ of heat. All of this heat was used to heat 500.0 g of water that had an initial temperature of 20.0/C. What was the final temperature of the water?
Answer: 70.0°C
Explanation:
Quantity of heat = Mass * Specific heat * Change in temperature
Quantity of heat = 104.6 KJ
Mass = 500.0 g
Specific heat of water is 4.18 J/g°C
Change in temperature assuming final temperature is x = x - 20
Units should be in grams and joules:
104,600 = 500 * 4.18 * (x - 20)
104,600 = 2,090 * (x - 20)
x - 20 = 104,600/2,090
x = 104,600/2,090 + 20
x = 69.8
= 70.0°C
1.How many miles of water does a raindrop contain if it has a mass of 0.060g?
2.What mass of water would you need to have 15 moles of H20?
3.A container of Trader Joe’s sea salt contains 750 grams.How many miles of sodium chloride (NaCl) is this?
4. A cake recipe calls for 0.080 moles of baking soda (NAHCO3).What mass should the chef measure out?
5. The chemical formula for rust is Fe203. If the total mass of rust on a 1967 Chevy corvette is 190 kg, how many moles is that?
Answer:
1. 0.0033 moles of water.
2. 270g of water
3. 12.8g NaCl
4. 6.72g NaHCO3
5. 1190moles Fe2O3
Explanation:
To convert moles to grams or vice versa we require tu use molar mass of the substance as follows:
1. Molar mass water: 18g/mol
0.060g * (1mol / 18g) = 0.0033 moles of water
2. Molar mass water: 18g/mol
15 moles H₂O * (18g / 1mol) = 270g of water
3. We can assume all sea salt is NaCl -Molar mass: 58.44g/mol-
750g NaCl * (1mol / 58.44g) = 12.8g of NaCl
4. Molar mass NaHCO₃: 84g/mol:
0.080mol * (84g/mol) = 6.72g NaHCO3
5. Molar mass Fe2O3: 159.69g/mol:
190kg = 190000g * (1mol / 159.69g) = 1190moles Fe2O3
Why Do Some Things Stop While Others Keep Going?
Answer:because they run out of energy when it is transferred and to other objects, or their kinetic energy
Explanation:
What are some properties we can use to describe matter
Answer:
melting point, hardness, odor, temperature
A student is drinking a cup of hot chocolate as they sit by a campfire on a chilly evening. They know that the cup of hot chocolate transfers thermal energy to the surrounding air. The heated air over their cup of hot chocolate expands and rises and is replaced by cooler, denser air.
This method of energy transfer is —
Answer:
A student is drinking a cup of hot chocolate as they sit by a campfire on a chilly evening. They know that the cup of hot chocolate transfers thermal energy to the surrounding air. The heated air over their cup of hot chocolate expands and rises and is replaced by cooler, denser air.
This method of energy transfer is
Explanation:
Answer:
radiation
Explanation:
radiation is when an existing heat source spreads heat to its surroundings
why is magneisum a metal
Answer:
Chemical element, metallic, symbol Mg, situated in group IIa in the periodic table, atomic number: 12, atomic weight: 24,312. ... Magnesium is known for a long time as the lighter structural metal in the industry, due to it's low weight and to it's capability of forming mechanically resistant alloys.
2. Just like the N and S poles on bar
magnets, electrons and protons
each other.
A. attract
B. repel
C. repulse
D. push apart
Answer:
A) attract
Explanation:
hope it helps you
To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. Therefore, the correct option is option A.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron. Just like the N and S poles on bar magnets, electrons and protons attract each other.
Therefore, the correct option is option A.
To know more about atom, here:
https://brainly.com/question/13518322
#SPJ2
____ Al(NO3)3 + ____ FeCl2 --> _____ Fe(NO3)2 + ______AlCl3
~
how to fix/ balance this chemical reaction?
The balanced equation
2Al(NO₃)₃ + 3FeCl₂ ⇒ 3Fe(NO₃)₂ + 2AlCl₃
Further explanationGiven
Reaction
Al(NO₃)₃ + FeCl₂ --> Fe(NO₃)₂ + AlCl₃
Required
Balanced equation
Solution
Give a coefficient
aAl(NO₃)₃ + bFeCl₂ --> Fe(NO₃)₂ + cAlCl₃
Make an equation
Fe, left=b, right=1⇒b=1
N, left=3a, right=2⇒3a=2⇒a=2/3
Cl, left=2b, right=3c⇒2b=3c⇒2.1=3c⇒c=2/3
The equation becomes :
2/3Al(NO₃)₃ + FeCl₂ --> Fe(NO₃)₂ + 2/3AlCl₃ x3
2Al(NO₃)₃ + 3FeCl₂ --> 3Fe(NO₃)₂ + 2AlCl₃
RODINNIS
COURSES
onal Science
Attempt 1 of 2
Which of the following distinctions are used to identify sedimentary rock? Select all that apply.
o where is was formed
conditions it was formed under
n when it was formed
what it is composed of
how many layers it consists of
NEED HELP ASAP (check the picture)
where it was formed and. conditions it was formed under
What is this equation balanced?
CH4 + 2O2 =》CO2 + 2H2O
Answer:
the balanced chemical reaction is provided above .
Explanation:
the given reaction is reaction of methane with oxygen ( or burning of methane in presence of oxygen )
it is highly exothermic, because high amount of heat is evolved in this reaction
explain how transferring energy into or out of a substance changes the molecules kinetic energy and changes their freedom of movement
Answer:
Transferring energy into or out of a substance changes its temperature, which changes the molecules' freedom of movement. Claim 2: Transferring energy into or out of a substance changes the molecules' kinetic energy, which changes their freedom of movement.
Organisms that make energy are called ____.
Answer:
Producers
Explanation:
An autotroph is an organism that can produce its own food using light, water, carbon dioxide, or other chemicals. Because autotrophs produce their own food, they are sometimes called producers.
How many grams are in 2.0 moles of iron(III) carbonate?
Explanation:
1 mole is equal to 1 moles Iron(III) or 832.29538 grams, so 2 moles Iron(III) = 1664.59076 grams
