Answer:
a 17 bc it is how it works
Girls are usually completely physically mature by 18 years old.
What is puberty ?Puberty refers to the physical transformation of a child's body into an adult one capable of fertile reproduction.
In girls puberty generally attains before two years earlier than the boys. And the exact age of the girls to attain puberty is in between the age of 10 to 14.
Hence the age of girls to attain puberty is 14.
To know more about puberty, visit the below link:
https://brainly.com/question/25821562
#SPJ2
2AI + 3H2SO4 -> Al2(SO4)3 + 3H2
How many grams of Al2(SO4)3 would be formed if 250g H2SO4 completely reacted with
aluminum?
2
181.2 g
313.8 g
273.7 g
201.9 g
Please help!!!!!
Answer:
B. 313.8
Explanation:
Can somebody that is good at science help me with these two questions? Please and thank you!
A compound is 39.97% carbon, 13.41% hydrogen, and 46.62% nitrogen. What is the empirical formula?
Answer:
CH4N
A compound is 39.97% carbon, 13.41% hydrogen, and 46.62% nitrogen.
Explanation:
Hope this helps.
Answer: CH4N is correct
Explanation:
39.97% carbon
13.41% hydrogen
46.62% nitrogen.
Which of the following equations of CH4 + Cl2
-
CCl4+ HCl is balanced?
A. O CH4 + Cl2 - CC14+ HCI
B.
CH4 + Cl2 - CCl4 + 4HCI
С.
CH4 + 4Cl2 - CCl4 + 4HCI
D
CH4 + 2Cl2 - CCl4 +2HCI
Balanced equation : C. CH₄ + 4Cl₂⇒ CCl₄+ 4HCl
Further explanationEqualization of chemical reactions can be done using variables. Steps in equalizing the reaction equation:
1. gives a coefficient on substances involved in the equation of reaction such as a, b, or c, etc.
2. make an equation based on the similarity of the number of atoms where the number of atoms = coefficient × index (subscript) between reactant and product
3. Select the coefficient of the substance with the most complex chemical formula equal to 1
Reaction
CH₄ + Cl₂⇒ CCl₄+ HCl
Give coefficient :aCH₄ + bCl₂⇒ CCl₄+ cHCl
Make equation :C, left=a, right=1⇒a=1
H, left=4a, right=c⇒4a=c⇒4.1=c⇒c=4
Cl, left=2b, right=4+c⇒2b=4+c⇒2b=4+4⇒2b=8⇒b=4
The equation becomes :
CH₄ + 4Cl₂⇒ CCl₄+ 4HCl
write the name of the first twenty elements with their symbols and their atomic number
Answer:
1 Hydrogen H
2 Helium He
3 Lithium Li
4 Beryllium Be
5 Boron B
6 Carbon C
7 Nitrogen N
8 Oxygen O
9 Fluorine F
10 Neon Ne
11 Sodium Na
12 Magnesium Mg
13 Aluminium Al
14 Silicon Si
15 Phosphorus P
16 Sulfur S
17 Chlorine Cl
18 Argon Ar
19 Potassium K
20. calcium Ca
Answer:
h - hydrogen (1)
he - helium (2)
li - lithium (3)
be - beryllium (4)
b - boron (5)
c - carbon (6)
n - nitrogen (7)
o - oxygen (8)
f - fluorine (9)
ne - neon (10)
na - sodium (11)
mg - magnesium (12)
al- aluminium (13)
si - silicon (14)
p - phosphorus (15)
s - sulfur (16)
cl - chlorine (17)
ar - argon (18)
k - potassium (19)
ca - calcium (20)
Make
a claim about why cells need ribosomes.
Summarize evidence to support the claim
and explain your reasoning.
ls?
Which of the following statements best describes the relationship between the elements phosphorus (P), arsenic (As) and bismuth (Bi)?
A. The elements are in the same period because they have the same numbers of energy levels, but different reactivity.
B. The elements are in the same group because they have the same numbers of energy levels, but different reactivity.
C. The elements are in the same period because they have similar reactivity and the same number of valence electrons.
D. The elements are in the same group because they have similar reactivity and the same number of valence electrons.
Answer:
A
Explanation:
WHATS THE DIFFERENCE BETWEEN MASS AND WEIGHT WELPPPPP
Answer:
Mass is amount of matter. Weight is how that matter is affected by gravity.
Explanation:
The chemical formula for the ionic compound aluminum sulfite is Al2(SO3)3. Explain why there are 2 cations for every 3 anions in this compound.
Answer:
Explanation:
While trying to write the chemical formula for a compound (a neutral molecule), one must identify and exchange the charge of the cation with that of the anion to become the subscript of one other. For example
Aluminium oxide has Aluminium (Al) and oxygen (O); since Al has a charge of 3+ (the cation) and O has a charge of 2- (the anion), the compound would have it's charges as Al³⁺O²⁻ and when the charges are exchanged to there subscripts, it would form Al₂O₃; thus there would be two cations of aluminium for every three anions of oxygen in order to have a neutral molecule.
This same explanation can be given to Aluminium sulfite. Aluminium sulfite has Aluminium (Al) and sulfite (SO₃). Al has a charge of 3+ (cation) while sulfite has a charge of 2- (anion), with the compound having it's charges as Al³⁺(SO₃)²⁻ and when the charges are exchanged to there subscripts, it would form Al₂(SO₃)₃ and would thus have 2 cations of aluminium (Al³⁺) for every 3 anions of sulfite (SO₃³⁻) in order to have a neutral molecule.
State the total number of electrons occupying all the p- orbitals in one atom of chlorine .
Answer:A chlorine atom in its ground state has a total of seven electrons in orbitals related to the atoms third energy level.
Explanation:
PLEASE HELP I WILL GIVE BRAINLIEST!!! Its due tonight at 12:00
Answer:
c
Explanation:
we have only distance vs time graph so c is the right answer that cart is moving with constant speed of 0.5m/s
confirmed
first calculate distance which is from 2 to 5.5
5.5-2=3.5
apply the formula of velocity
v=s/t
v=3.5/7=0.5
Answer:
Answer is C
Explanation:
v= 3.5/7 = 0.5
When an ionic bond forms what type of ions are joined?
Please answer correctly !!!!!!!!!!!!! Will mark Brianliest !!!!!!!!!!!!!!!!!
If you could answer any it would be deeply appreciated.
Answer:magnesium plus nitrogen is : magnesium nitride
Explanation:
what are the energy transformations taking place in your alarm clock
Answer:
Explanation:
The clock now has potential energy. When the alarm rings, the potential energy is converted into kinetic energy and sound energy.
Alarm clock runs due to the electrical energy. Due to the electric current, the electric motor rotates the blade. It means that the electrical energy is converted into mechanical energy.
The mechanical energy finally generates vibrations which cause sound.
Thus, energy transformation which takes place in alarm clock will follow the order-
Electrical to mechanical to sound.
Steel has a density of 7.8 g/cm3. What is the volume of a 78-gram piece of steel?
Answer:
10 cm³Explanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\[/tex]
From the question we have
[tex]volume = \frac{78}{7.8} \\ [/tex]
We have the final answer as
10 cm³Hope this helps you
picture *** pls help
The volume of Oxygen at STP required : 251.25 L
Further explanationConditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters/mol.
Reaction(combustion) :
2C₂H₂(g)+5O₂(g)⇒4CO₂(g)+2H₂O(g)
mol C₂H₂ :
[tex]\tt \dfrac{100.5}{22.4}=4.49[/tex]
mol ratio C₂H₂ : O₂ = 2 : 5, so mol O₂ :
[tex]\tt \dfrac{5}{2}\times 4.49=11.23[/tex]
volume O₂ at STP :
[tex]\tt 11.23\times 22.4=251.55~L[/tex]
Or you can use Avogadro's hypothesis :
In the same temperature and pressure, in the same volume conditions, the gas contains the same number of molecules
So the ratio of gas volume will be equal to the ratio of gas moles :
[tex]\tt \dfrac{V_1}{V_2}=\dfrac{n_1}{n_2}\\\\\dfrac{100.5}{V_2}=\dfrac{2}{5}\\\\V_2=\dfrac{100.5\times 5}{2}=251.25~L[/tex]
In the reaction 2AgI + Na2S → Ag2S +2NaI, calculate the number of moles of AgI needed to react with 85.0 g
Answer:
8.5gNaI × 1molNaI/78gNaI × 234.7g AgI / 1 MOL AgI × 2Mol Ag I / 1mol Na2S=51.2 g of AgI reacts with Na2 SExplanation:
conversion factor is used to make sure that all the units cancels with the other units and we only remain with the mass of Ag I which is 51.2g but since the number of moles can be calculated by dividing with the relative molecular mass therefore 51.2g/234.7gmol=0.22mol
true or false, during a change of state, the thermal energy gained or lost by a material changes the kinetic energy of its particles
Answer:
true..... not false okkkkk
Which choices are layers of the atmosphere?
Select the five correct answers.
Thermosphere
Meteorosphere
Croposphere
Stratosphere
Mesosphere
Danosphere
Exosphere
Troposphere
Answer:
Mesosphere
Stratosphere
Thermosphere
Troposphere
Exosphere
Explanation:
The exosphere refers to the farthest region of the atmosphere that gradually fades into space.
The troposphere is the lowest layer of atmosphere. It is the layer where weather changes occur.
The thermosphere is right above the mesosphere but just below the exosphere. It is the layer where photoionization/photodissociation of molecules occurs thereby creating ions. This largely owes to interaction of molecules in this layer with ultraviolet radiation.
The stratosphere is composed of gases. Prominent among them is ozone which serves as a blanket against the sun's ionizing radiation.
The mesosphere lies above the stratosphere but just below the thermosphere. Temperature decreases steadily with height in the mesosphere.
What would be one way to avoid static electricity? А) Dry cotton fabrics and synthetic fabrics separately. B) Run a metal clothes hanger across your dry hair. C Use a blow dryer to dry your hair. D Wear shoes with rubber soles.
Answer: The answer would be A.
Explanation:
Answer: B
Explanation:
RIGHT ANWSER WILL BE MARKED BRAINLIEST
Answer:
11460
Explanation:
Where v stands for __________________________________ and the units are meters per second (m/s).
Answer:
Velocity
Explanation:
Answer: velocity I’m sure
Explanation:
Which statement is true about molarity and percent by mass? (3 points)
Molarity is the amount of solute in 1L of solution while percent by mass is the ratio of the mass solute to the mass of solution multiplied by 100. Both quantities are used measure the amount of solute in solution.
What is molarity and percent by mass?The question is incomplete however, I will try to explain molarity and percent by mass.
The term molarity means the number of moles of a substance is 1 L of solution while the percent by mass is the ratio of the mass solute to the mass of solution multiplied by 100.
Both molarity and percent by mass shows the amount of solute in a solution.
Learn more about molarity: https://brainly.com/question/12127540
Answer:
Both are ratios of the amount of solute over the amount of solution/
Explanation:
took test.
What is that Molar mass of ammonium phosphite?
Answer:
149.09 g/mol GOOD LESSONS ♡
Answer:
The answer is 149.09 g/mol
Explanation:
I hope this helps!!
how does atomic radius affect coulombic attraction?
Which ion would represent the ion of an element from Group 2A?
A2+
Y3+
X2-
Z+
Answer:
A2+
..........
Explanation:
they lose 2 electrons to form an ion
What quantity is needed to convert between the moles of a
given sample of a substance and its mass in grams?
a the molar mass of the substance
b the density of the substance
с
the physical state of the substance
d all of the above
Check it
Answer:
a
the molar mass of the substance
Answer: a
The molar mass of the substance
Explanation:
A sample of gas is stored at 15 atmosphere and has a volume of 5 liters.If the volume of the gas is reduced to 3 liters,what will the new pressure be?
The new pressure will be : 25 atm
Further explanationBoyle's Law
At a constant temperature, the gas volume is inversely proportional to the pressure applied
[tex]\rm p_1V_1=p_2.V_2\\\\\dfrac{p_1}{p_2}=\dfrac{V_2}{V_1}[/tex]
P₁=15 atm
V₁=5 L
V₂= 3 L
[tex]\tt P_2=\dfrac{P_1.V_1}{V_2}\\\\P_1=\dfrac{15~atm\times 5~L}{3~L}\\\\P_1=\boxed{\bold{25~atm}}[/tex]
what happens if the temperature of a system at equilibrium is increased?