Answer:
cells arose from preexisting cells
Explanation:
Rudolph Virchow is a German biologist that built on the work of other scientists such as Theodor Schwan to contribute his own quota to the development of the cell theory as it is currently known.
After several studies, Virchow rejected the idea of spontaneous generation and accepted the initially rejected idea of cell division. He earlier believed that cell division only takes place is some special type of cells and not in all cells.
Even though Virchow was not the first to bring the idea of cells arising from preexisting cells, he was the one that popularized the idea and added it to the earlier belief that all living organisms are made up of cells.
Answer:
B
Explanation:
P= f/a solve it for f
Answer:
Force = Pressure × Area
Explanation:
Easy, just invert the equation. Transpose the force variable over to the left of the equals sign, and transpose the pressure variable back to the right side.
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Answer:
wat
Explanation:
Answer:
Basic ABCHope it helps..What u learned about the states of matter?
Answer:t
Explanation:
In everyday life, four states of matter are visible: solid, liquid, gas, and plasma.
Of course, matter also has other states, such as Bose-Einstein density and Fermion density, but these states are only observed under certain conditions.
Can you answer Chemistry means in wide?
Answer:
Chemistry is a branch of a science which explain about study of composion properties and the transformation or change of matter.
SOMEONE PLEASE HELP HURRY
I think the answer is A. I know it's Planet X.
An atom of nitrogen has seven electrons. Which diagram correctly represents the arrangement of these electrons?
ОА.
OB
1112
1s 11:28 1111
2p
1s 12
2p
1s 12
12s 2p
OD. 1111s 112s
112p
Ос.
Answer:
Option C.
Explanation:
The arrangement of electrons in their orbital follows certain rules.
The Hund's rule practically explained how electrons are distributed in their orbitals.
The Hund's rule states that electrons distributed among the orbitals of the same shell singly (without partner) before pairing occurs.
In the filling of these electrons in their orbitals, we fill in the electron without pairing first because electrons tends to repel each other before filling with the opposite spin as shown in the attached photo.
Why are ionic crystals soluble in water?
A. The covalent bonds in the ionic crystal can easily reshape to bond with the water molecules, allowing it to dissolve.
B. The water slides the layers of the ionic crystal lattice so that positive charges line up with positive charges. They repel
each other and break the crystal apart.
C. Partial charges in water molecules attract the charges in the atoms of the ionic crystal, pulling the atoms off the crystal.
D. They are not. The positive and negative charges in the ionic lattice are stronger than the partial charges in the water.
Answer:
C. Partial charges in water molecules attract the charges in the atoms of the ionic crystal, pulling the atoms off the crystal.
Explanation:
Water consists of partial positive and hydrogen ions and partial negative oxygen ions. The ionic crystals also dissociate into ions when in water.These partial charges and ability of ionic compounds to dissociate in water are the main reason why ionic crystals dissolve in water.
The partial charges in the water molecules form a strong attraction towards the charges in the atoms of ionic crystals. This then pulls the atoms from the crystals and ends up in the dissolution of the ionic crystals.
A chemical equation is balanced when Group of answer choices the number of atoms of each element is the same in reactants and products. the charge on each atom is the same in reactants and products. the sum of the coefficients of the reactants is equal to the sum of the coefficients of the products. the total number of ions is the same in reactants and products. the total number of molecules is the same in reactants and products.
Answer:
a
Explanation:
A chemical equation is said to balanced only when the number of atoms of each element is the same in both reactants and products side. Rest all options are absurd. Hence, option a is correct.
Balancing of the reaction has no relation with coefficient, molecules or charge of the elements
compare the activity of sodium and iron with water and dilute acid
Answer:
Reactions of sodium with water and dilute acid
Sodium reacts explosively with dilute HCl(aq) to produce NaCl(aq) and H₂(g)
2Na (s) + 2HCl(aq) → 2NaCl(aq) + H₂(g)
Sodium reacts violently with cold water to produce NaOH(aq) and H₂(g)
2Na (s) + H₂O(l) → 2Na(OH)(aq) + H₂(g)
The produced hydrogen may become ignited and explode
Reactions of iron with water and dilute acid
Iron reacts very slowly with dilute acid to produce iron (II) chloride and hydrogen gas
Fe (s) + 2 HCl (aq) → FeCl₂ (aq) + H₂ (g)
Iron does not react with cold water. Iron reacts only with steam
Explanation:
Read ""the Ozone Hole"" and answer the question below list at least three scientific disciplines related to chemistry mentioned or alluded to in the article
Answer:
Any 3 of the following:
atmospheric science
environmental science
climate science
biology
astronomy
human physiology and medicine
Explanation:
Got it right on edge 23
A straight chain hydrocarbon with the formula C^3H^4 _____.
has a triple C-C bond
has a double C-C bond
is essentially inert
has two double C-C bonds
Answer:
has two double C-C bonds
Explanation:
A saturated compound is a compound having the full complement of hydrogen atoms for every carbon atom while an unsaturated compound does not contain the full complement of hydrogen atoms for every atom of carbon.
If we look at C3H4, the only possible structure of the compound is H2C=C=CH2. We can see from this arrangement that the compound contains a cumulative double bond. This is the specific structure that fits into one of the descriptions in the options, the compound contains two double bonds.
1s 2s22p63s23p4
How many valence electrons does this atom have?
2
6
4
12
Answer:
6
Explanation:
How many valence electrons does this atom have?
answer 6
Answer:
6.
Sulphur has 6 valence electrons.
( .°. that's the electronic configuration of sulphur .)
in order to decrease the freezing point of 500. g of water to 1.00° c how many grams of ethylene glycol (C2H602)must be added (KF=1.86°C kg solvent)
Answer:
if wrong sorry ok????
The substances are placed in separate containers at room temperature, and each container is gradually cooled. Which of these substances will solidify before the temperature reaches 0°C? benzene water butane nitrogen
Answer:
Benzene
Explanation:
You have to find the freezing point for each of these (make sure they're in Celsius). You might want to double check these but:
Benzene: 5.5
Water: 0
Butane: -138
Nitrogen: -210
The substances that will solidify before the temperature reaches 0°C is benzene. The correct option is A.
What is freezing point?Freezing, also known as solidification, is a phase transition that occurs when the temperature of a liquid falls below its freezing point.
If the intermolecular forces between its molecules are strong, the freezing point is high.
When the forces are weak, the freezing point is low. The freezing point of a liquid or the melting point of a solid occurs when the solid and liquid phases are in equilibrium.
Pure benzene has a freezing point of 5.48 degrees Celsius. Because of the salt in it, fresh water freezes at 32 degrees Fahrenheit, but seawater freezes at around 28.4 degrees Fahrenheit.
Thus, as per the given scenario, the correct option is A.
For more details regarding freezing, visit:
https://brainly.com/question/3121416
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name Two soft metals which can be cut with a knife.
Answer:
lithium, and sodium can be cut with a knife
In a chemical equation, the symbol that means "dissolved in water" is _____. (s) (l) (aq) (g)
What is 9.871 x 10^-3 in standard form? *
Answer:
0.009871
Explanation:
[tex] 9.871\times 10^{-3} = 0.009871[/tex]
Answer:
.009871
Explanation:
Which are the physical properties of water
Answer:
Some physical properties of water:
It is odorless.It could appear as a white crystalline solid in solid form, a transparent gas with almost no color but a slight hint of blue in liquid form, or a colorless gas in gas form.It has a melting point of 0°C and a boiling point of 100°C.Its density (at 25°C) is about 0.99701 grams/cm³.It has a viscosity of 0.8903 centi-poise.Of course, there are many more but these are some common ones.
Which type of bonds can carbon atoms form with other carbon atoms? (1 point)
O double, triple, and quadruple bonds
O single and double bonds
O double and triple bonds
O single, double, and triple bonds
Answer:
single, double, and triple bonds
What is the atomic number of neon?
Answer:
the atomic number of a neon is 10
45. The following data was collected for 3 compounds:
Mass of Nitrogen that combines with 1 g of Oxygen
Compound A 1.750 g
Compound B 0.8750 g
Compound C 0.4375 g
Show whether these are the same or different compounds. What chemical law is being observed here?
Answer:
The three compounds are different compounds
Explanation:
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound A = 1.750 g
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound B = 0.8750 g
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound C = 0.4375 g
According to the law of multiple proportions, when atoms of two different elements react to form compounds, the masses of one of the elements that combines with a fixed mass of the other element are in small whole number ratios.
The ratio of the masses are;
Mass of Nitrogen in Compound B/(Mass of Nitrogen in Compound C = 0.8750/0.4375 = 2
Mass of Nitrogen in Compound A/(Mass of Nitrogen in Compound C = 1.750/0.4375= 4
Mass of Nitrogen in Compound A/(Mass of Nitrogen in Compound B = 1.750/0.8750= 2
Given that the masses of Nitrogen in the three compounds are in small whole number ratios, the three compounds, Compound A, Compound B, and Compound C are different compounds.
PLEASE HELP WILL GIVE BRAINLIEST!!!!
If the concentration of substance A of a reversible reaction in dynamic equilibrium increases, how will the equilibrium change?
A. It will shift to create more of substance A.
B. It will shift towards the reactants.
C. It will shift towards the products.
D. It will shift to create less of substance A.
Answer:
[tex]\boxed{It\ will\ shift\ to\ create\ less\ of\ substance\ A}[/tex]
Explanation:
If the concentration of any substance A in a dynamic equilibrium increases, The equilibrium will be shifted to its opposite side so that Substance A can be created less and the substance opposite to A can be created more so that a "dynamic equilibrium" can again be established.
why scientist use the international system of units
Explanation:
it allows scientists from disparate regions to use a single standard in communicating scientific data without vocabulary confusion.
A star is estimated to have a mass of 2.0 x 10 ^36kg. Assuming it to be a sphere of average radius of 7.0 x 10 ^5 km. Calculate the average density of the star in g/cm^3 and in lb/ft^3
Answer:
a) 1.392 x 10^6 g/cm^3
b) 8.69 x 10^7 lb/ft^3
Explanation:
mass of the star m = 2.0 x 10^36 kg
radius of the star (assumed to be spherical) r = 7.0 x 10^5 km = 7.0 x 10^8 m
The density of substance ρ = mass/volume
The volume of the star = volume of a sphere = [tex]\frac{4}{3}\pi r^{3}[/tex]
==> V = [tex]\frac{4}{3}*3.142*(7.0*10^8)^{3}[/tex] = 1.437 x 10^27 m^3
density of the star ρ = (2.0 x 10^36)/(1.437 x 10^27) = 1.392 x 10^9 kg/m^3
in g/cm^3 = (1.392 x 10^9)/1000 = 1.392 x 10^6 g/cm^3
in lb/ft^3 = (1.392 x 10^9)/16.018 = 8.69 x 10^7 lb/ft^3
Determinación de pH Expresa las siguientes concentraciones de [H+ ] en función del pH • [H+] = 0.001 M • [H+] = 0.002 M • [H+] = 2.45X10-4 M • [H+] = 5.2X10-9 M • [H+] = 0.04 M
Answer:
• pH = 3.0
• pH = 2.70
• pH = 3.61
• pH = 8.28
• pH = 1.40
Explanation:
El pH es una medida en química usada para determinar el grado de acidez o basicidad en una solución.
Se define como:
pH = -log₁₀ [H⁺]
El - logaritmo de la concentración molar de H⁺
Para las concentraciones de H⁺ dadas:
• [H+] = 0.001 M
pH = -log (0.001M) = 3
pH = 3.0
• [H+] = 0.002 M
pH = -log (0.002M)
pH = 2.70
• [H+] = 2.45X10-4 M
pH = -log (2.45X10-4 M )
pH = 3.61
• [H+] = 5.2X10-9 M
pH = -log (5.2X10-9 M)
pH = 8.28
• [H+] = 0.04 M
pH = -log (0.04M)
pH = 1.40
Which statement about Schrödinger’s theory of the atomic model is true?
Answer:
it explain odds of finding the position of an electron.
What is the main factor responsible for the acidic and basic character of oxides?
Explain your answer.
Explanation:
We define non-metal oxide acidity in terms of the acidic solutions formed in reactions with water. For example, sulfur trioxide reacts with water to forms sulfuric acid. In sum, acidic oxides are oxides of non-metals, and basic oxides are oxides of metals. ... CrO is basic, Cr2O3 is amphoteric and CrO3 is acidic.Reply me in commentsChemical change example
Answer: burning paper
Explanation:
The paper burns in air to form smoke and ash. which makes it a chemical change.
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Answer:
1. 3-methylpentane
2. 2-bromo-3-chloropentane
3. 2,2,4-trimethylpentane
Explanation:
1. CH3CH2CH(CH3)CH2CH3.
Methyl group is in the third carbon atom in the long chain. The organic compound has five(5) carbon atoms thus it is named as pentane.
Therefore the name of the compound is
3-methylpentane
2. CH3CH(Br)CH(Cl)CH2CH3
The compound has Chlorine and Bromine in the carbon chain. Chlorine is given as chloro-, Bromine is given as bromo, depending on the position in the carbon chain. Bromine is located in 2 carbon atom and chlorine is in third(3) carbon atom in the long chain. The long chain has five carbon atoms thus pentane.
Naming of the compound we begin with the on lowest in the alphabet. The name of the organic compound is therefore;
2-bromo-3-chloropentane
3. CH3CH(CH3)3CH(CH3)CH2CH3
In this long chained organic compound, methyl-group is found in 2,2 and 4th positions. Since this is still pentane, naming the organic compounds, we start with the one with the lowest carbon. Therefore this becomes;
2,2,4-trimethylpentane
I hope this helps you to know how to name the organic compounds.
Hydrogen bromide is found in volcanic gas. What is the chemical formula for
this compound?
Answer:
Hydrogen bromide, anhydrous appears as a colorless gas with a pungent irritating odor. Corrosive. Heavier than air. Prolonged exposure to fire or intense heat may result in the violent rupture and rocketing of the container. Long-term exposure to low concentrations or short-term exposure to high concentrations can result in adverse health effects from inhalation. Used to make other chemicals and as a catalyst in the manufacture of chemicals. Rate of onset: Immediate Persistence: Minutes to hours Odor threshold: 2 ppm Source/use/other hazard: Chemical manufacturing industry; very corrosive.
Explanation:
HBr