Explanation:
Radium(Ra)=>atomic number=88
BERYLLIUM (Be)=>atomic number =4
why is Ra larger than Be
1. since the atomic number of Ra is greater than Be, the number of electrons is more, which means there are more number of shells present in Ra than Be. (atomic Radius)2. the more the valence electron (excluding fully filled ones) the less is the nuclear attraction forcesince Ra has more valence electron in its outermost shell, the nuclear attraction force is less which means that Ra 's size is greater than Be.hope it helps:)
I have two beakers (A & B) containing clear liquids. The first one (A) holds 75g and after being analyzed proves to contain 4.425g of hydrogen and 70.575g of oxygen. The second beaker (B) holds 125g and analysis shows that it is composed of 7.38g of hydrogen and 117.6g of oxygen.
Answer:
The solutions are most likely hydrogen peroxide since it is the compound of hydrogen and oxygen that has a ratio of Hydrogen to Oxygen ratio of 1 : 1.
Note:The question is not complete.
Explanation:
The empirical formula of the two compounds are determined
Solution in beaker A:
Mass of Hydrogen = 4.425 g
Moles of hydrogen = reacting mass/molar mass = 4.425 g / 1 g/mol = 4.425 moles
Mass of oxygen = 70.575 g
Moles of oxygen = reacting mass/molar mass = 70.575 g / 16 g/mol= 4.411 moles
Mole ratio of Hydrogen to Oxygen = 4.425 : 4.411
Simplest mole ratio = 1 : 1
Therefore, empirical formula of solution in A = H₁O₁
Solution in beaker B:
Mass of Hydrogen = 7.38 g
Moles of hydrogen = reacting mass/molar mass = 7.38 g / 1 g/mol = 7.38 moles
Mass of oxygen = 117.6 g
Moles of oxygen = reacting mass/molar mass = 117.6 g / 16 g/mol= 7.35 moles
Mole ratio of Hydrogen to Oxygen = 7.38 : 7.35
Simplest mole ratio = 1 : 1
Therefore, empirical formula of solution in B = H₁O₁
The solutions in beakers A and B have the same empirical formula. Their molecular masses are not given, so their molecular formula is not certain. However, the solutions are most likely hydrogen peroxide since it is the compound of hydrogen and oxygen that has a ratio of Hydrogen to Oxygen ratio of 1 : 1.
if 2g of potassium are added to 50g of water, what mass of h2 is produced
Answer:
1950 grams
Explanation: The mass of potassium that must react with water to produce 50.0 grams of H2 is 1950 grams
C6H12O6 + 6O2 → 6CO2 + ? H2O + energy
Whats the answer? I really don't know,
Answer: C. 6
Explanation:
According to the Law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical reaction for photosynthesis is :
[tex]C_6H_{12}O_6+6O_2\rightarrow 6CO_2+6H_2O+energy[/tex]
Thus the coefficient of water is 6.
PLS ANSWER THESE 3 QUESTIONS WHICHEVER YOU KNOW!!
1.For an object at rest, the normal force equals the gravitational force. What is the sum of these forces called?
·ω·
A Net force
B Unbalanced force
C Inertia
D Potential force
2. Which of the following best describes the forces when there are different-sized forces from opposite directions acting on an object?
a Positive
b Negative
c Unbalanced
d Gravitational
3. An object is at rest on a table. The gravitational force is 10 N down, and the normal force is 10 N up. What is the net force?
An object at rest on a table. An arrow pointing down represents 10 newtons of gravitational force. An arrow pointing up represents 10 newtons of normal force.
a 10 N up
b 0 N
c 10 N down
d 20 N up
Answer:
I only know 3 its 0 N because 10-8=2 and 2-2=0
Explanation 10-8=2 2-2=0
All the following are compounds except. A.water. B.sugar solution. C.aqueous. D.sulphur dioxide
Answer:
B.sugar solution
Explanation:
A sugar solution is not a compound.
Rather, the solution is a mixture and an impure substance.
A compound is composed of two or more kinds of atoms or elements joined in a definite grouping .The properties of the compound is distinct from those of the individual atoms that makes them. Sugar solution is sugar and waterIt is made up of two compounds not chemically combined.1 point
2. If a 10.0 L balloon expands to 20.0 L when the pressure is at 2.0 atm,
then determine the final pressure of the balloon as temperature is held
constant
Answer:
1 atmExplanation:
The final pressure can be found by using the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
Since we are finding the new pressure
[tex]P_2 = \frac{P_1V_1}{V_2} \\[/tex]
From the question we have
[tex]P_2 = \frac{10 \times 2}{20} = \frac{20}{20} \\ [/tex]
We have the final answer as
1 atmHope this helps you
ASAP pleaseee and Thankyou
options:
genotype
phenotype
Answer:
phenotype then genotype
Explanation:
phenotype is observable traits, genotype is heritable genes that can be passed down
Which is the best description of a molecule?
A molecule of an element is composed of at least two types of atoms.
A molecule of a compound is composed of only one type of atom.
A molecule of a compound is composed of at least two types of atoms.
A molecule of an element is composed of exactly two types of atoms.
Answer:
The third option "A molecule of a compound is composed of at least two types of atoms" is correct
Explanation:
This question isn't about molecules, it's about elements and compounds.
Elements are made of one and only one type of atoms, while compounds are made of more than one type of atoms.
(Molecules are just groups of atoms, it doesn't matter what they're made of)
Answer:
a
Explanation:
Define these three words in your own words. will also give brainliest.
1.air resistance
2.Data
3.Magnetism
Answer:
Translation: Air resistance is a force that is caused by air. The force acts in the opposite direction to an object moving through the air.
Data are characteristics or information, usually numerical, that are collected through observation. In a more technical sense, data are a set of values of qualitative or quantitative variables about one or more persons or objects, while a datum (singular of data) is a single value of a single variable.
a physical phenomenon produced by the motion of electric charge, which results in attractive and repulsive forces between objects.
Which of these is an example of a description of
speed?
An airplane traveled west from New York to Los
Angeles.
A train traveled east at 200 mph from Albuquerque to
Dallas.
The average Olympic sprinter runs 8 m/s.
An apple fell from the tree and then rolled 1 m north.
Answer:
The average Olympic sprinter runs 8 m/s.
Explanation:
Speed is defined as the change of an object from one position to another position with respect to the time taken. It is independent of direction and only depends on the change of its position.
In the context, all the other sentences has direction mentioned in the sentence except the sentence "the average Olympic sprinter runs 8 m/s". In this sentence, the speed of an Olympic sprinter id given i.e. 8 meter per second.
Which of the following is evidence that groundwater cause erosion and deposition
Answer:You didn't provide examples
Explanation: Groundwater can cause erosion under the surface as it moves through the soil. During the movement an acid is formed which what causes erosion and deposition.
Hope that helps
why do magnets move objects in different ways
Answer:
Each magnet has a north and south end. Only opposite ends can attract, But if the ends are the same, they push away from each other. Magnets in some engines make it spin in a certain direction.
When should you avoid looking directly at magnesium burning?
Answer:
Magnesium also reacts with nitrogen in the air to produce some magnesium nitride (Mg3N2). Safety: Do not look directly at the burning magnesium due to the intensity of the light. A dry-powder fire extinguisher should be available. Disposal: Once cooled the solid magnesium products can be thrown in the trash.
Explanation:
In which direction will the electrons be pulled in the bond between hydrogen and chlorine?
toward the chlorine atom
toward both atoms equally
sometimes toward chlorine and sometimes toward hydrogen
toward the hydrogen atom
Answer:
toward the hydrogen atom
Explanation:
Answer:
toward the chlorine atom.
Explanation:
took the quiz and got it correct :)
0.0278, how many significant figures
Answer:
There are three significant figures
Explanation:
When counting sig figs you don't count the zeros unless it is between a number greater than zero. The two zeros aren't between the greater numbers so there are only 3.
A meterorite has velocity of 1544 m/s and a mass of 45 kg. Find its momentum
Answer:
69,480 kg.m/sExplanation:
The momentum of an object can be found by using the formula
momentum = mass × velocity
From the question we have
momentum = 45 × 1544
We have the final answer as
69,480 kg.m/sHope this helps you
Answer:
69,480 kg. m/s
have a nice day!
PLEASE I NEED HELP!!!Using the table below, identify the unknown material that has a mass of 15,06 g and a
volume of 0.78 mL.
Substance Density (g/cm) Substance
Ice (0°C) 0.917 Human fat
Water (4.0°C) 1.0000 Cork
Gold
1931
Table sugar
Helium (25°C)
0.000 164 Balsa wood
Air (25°C) 0.001 185 Earth
Density (g/cm)
0.94
0.22-0.26
159
0.12
554
Ice
Water
Gold
Helium
O Air
The unknown material : gold
Further explanationDensity is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:
[tex]\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}[/tex]
ρ = density
m = mass
v = volume
mass of unknown material : 15.06 g
volume : 0.78 ml
The density of unknown material :
[tex]\tt \rho=\dfrac{15.06}{0.78}\\\\\rho=19.31~g/ml[/tex]
Materials that match the density: gold
Which element forms an ion that is larger than its atom
Answer:
Electronegative element form anion that is larger than its neutral atom like fluorine F-
Explanation:
Which statement best explains why protons are used
to identify an element?
Answer:
Every atom of an element will have the same number of protons
Explanation:
Protons are used to identify an element because every atom of an element will have the same number of protons.
Protons are the positively charged particles found in an atom. They are called the atomic numberEvery atom of an element has the same number of protons. An element can have different atom in form of isotopes. These isotopes are only identifiable by the number of protons they have.put the following in order from LARGEST TO SMALLEST nuclueus,molecule,electron,atom,proton and a teacher
Answer:
electron, proton, nucleus, atom, molecule teacher
Calculate the concentration of hydrogen ion of a sample of vinegar with pH 6.82
The concentration of hydrogen ion of a sample of vinegar : 1.514 x 10⁻⁷
Further explanationpH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.
So that the two quantities between pH and [H⁺] are inversely proportional because they are associated with negative values.
A solution whose value is different by n has a difference in the concentration of H⁺ ion of 10ⁿ.
pH = - log [H⁺]
pH of a sample vinegar = 6.82
The concentration of hydrogen ion :
[tex]\tt 6.82=-log[H^+]\\\\(H^+]=10^{-6.82}=1.514\times 10^{-7}[/tex]
Which force helps food move through the large intestine during digestion?
A Muscle contractions exert a pushing force on the food.
B Oxygen molecules exert a pulling force on the food.
C Gravity exerts an upward pushing force on the food.
D Water exerts an upward pushing force on the food.
Answer:
The answer is A
Explanation:
Pls put me as brainliest
The force helps food move through the large intestine during digestion is muscle contractions exert a pushing force on the food. Thus option A is correct.
What is force?Force is defined as a push or pull upon any object resulting from the object's interaction with another object. It is a vector quantity.
Force can also be defined as an external cause that, when applied, changes or tends to change the state of the body, if the body is in motion.
Force is expressed as
Force = mass x acceleration
There are five types of force
Gravitational forceElectric forceMagnetic forceNuclear forceFrictional forceDigestion is define as the breakdown of food into smaller component that can be absorbed into blood streams.
Thus, the force helps food move through the large intestine during digestion is muscle contractions exert a pushing force on the food. Thus option A is correct.
To learn more about force, refer to the link below:
https://brainly.com/question/13191643
#SPJ5
complete the puzzle below by identifying the four type of speech context and two types of interpersonal communication evident in the presented situation
i need help with the je that asks which parent actually determines the sex the child
Answer:
Actually it is father who actually determine the sex of child
Explanation:
Because father has X & Y chromosome but mother has only XX chromosome. So it depends on which chromosome of father. If father's gamete has only x chromosome then the child will be female. And if the father's gamete has Y chromosome then the child will be male.
please mark me brainliest and 5 star
In your own words, please write a paragraph explaining what chemical and physical properties of elements mean.
Answer:
If this anwser helped you mark it the brainest please
Explanation:
Properties are features, qualities or characteristics of an item. Properties shall be used to classify the components. Properties are the attributes of a material that separates it from another substance. These properties are called physical properties and chemical properties in chemistry.
which two sentences taken together provide the best evidence to support the ideas that both physical and chemical change can significantly change the appearance of a substance ?
A. in a physical change the material involved is structurally the same before and after the change
B. a piece of metal may be heated in a fire until it glows but the metal is the same material before Heating and after Cooling
C. chemical changes require the breaking and forming of chemical bonds during a chemical reaction
D. the creation of a new ,solid substance from to liquid substance into the kids that a reaction has taken place that has alerted the original substance
Answer:
A ithink
Explanation:
The chemical changes require the breaking and forming of chemical bonds during a chemical reaction. The correct option is C.
What is chemical bond?Chemical Bonding refers to the formation of a chemical bond between two or more atoms, molecules, or ions to give rise to a chemical compound.
These chemical bonds are what hold the atoms in the resulting compound together.
A chemical bond is a bond formed when the atoms in a compound's molecule combine and are held together by a strong combining force.
Chemical bonds are classified into two types namely ionic bonds and covalent bonds.
Chemical bonding enables scientists to combine the elements of the periodic table in a variety of ways to create chemical compounds and materials.
Thus, the correct option is C.
For more details regarding chemical change, visit:
https://brainly.com/question/23693316
#SPJ2
At 5 atmosphere pressure, the volume of a gas is 1200 ml. What pressure is required to reduce
the volume of a gas to 2000 ml without changing the temperature?
Answer:
3 atmExplanation:
The new pressure can be found by using the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
Since we are finding the new pressure
[tex]P_2 = \frac{P_1V_1}{V_2} \\[/tex]
From the question we have
[tex]P_2 = \frac{5 \times 1200}{2000} = \frac{6000}{2000} = \frac{6}{2} = 3 \\ [/tex]
We have the final answer as
3 atmHope this helps you
Rashid belays net worth
I need help fast!!! Fill in the coefficients
Answer:
2HCl - H2 + Cl2
Explanation:
The two hydrochloric acid molecules decompose into one hydrogen molecule (H2) and one chlorine molecule (Cl2). If there is only one type of a specific molecule present, you should not have to add a coefficient of 1 behind it.
You dissolve 8.65 grams of lead(II) nitrate in water, and then you add 2.50 grams of aluminum. This reaction occurs: 2Al(s) + 3Pb(NO3)2(aq) → 3Pb(s) + 2Al(NO3)3(aq). What’s the theoretical yield of solid lead? Use the ideal gas resource and the periodic table. A. 5.41 g B. 11.2 g C. 19.2 g D. 28.8 g Reset
Answer: A. 5.41
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} Al=\frac{2.50g}{27g/mol}=0.0926moles[/tex]
[tex]\text{Moles of} Pb(NO_3)_2=\frac{8.65g}{331g/mol}=0.0261moles[/tex]
[tex]2Al(s)+3Pb(NO_3)_2(aq)\rightarrow 3Pb(s)+2Al(NO_3)_3(aq)[/tex]
According to stoichiometry :
3 moles of [tex]Pb(NO_3)_2[/tex] require = 2 moles of [tex]Al[/tex]
Thus 0.0261 moles of [tex]Pb(NO_3)_2[/tex] will require=[tex]\frac{2}{3}\times 0.0261=0.0174moles[/tex] of [tex]Al[/tex]
Thus [tex]Pb(NO_3)_2[/tex] is the limiting reagent as it limits the formation of product and [tex]Al[/tex] is the excess reagent.
As 3 moles of [tex]Pb(NO_3)_2[/tex] give = 3 moles of [tex]Pb[/tex]
Thus 0.0261 moles of [tex]Pb(NO_3)_2[/tex] give =[tex]\frac{3}{3}\times 0.0261=0.0261 moles[/tex] of [tex]Pb[/tex]
Mass of [tex]Pb=moles\times {\text {Molar mass}}=0.0261moles\times 207g/mol=5.41g[/tex]
Thus 5.41 g of solid lead will be produced from the given masses of both reactants.