Answer:
The numerical value for the acceleration of gravity is most accurately known as 9.8 m/s/s.
It took 25 seconds for a horse to complete a 400 meter race. What was the speed of the horse?
Answer:
v = 16 m/s
Explanation:
Given that,
Distance, d = 400 m
Time taken, t = 25 s
We need to find the speed of the horse. Speed is equal to distance covered divided by time taken. So,
[tex]v=\dfrac{d}{t}\\\\v=\dfrac{400\ m}{25\ s}\\\\v=16\ m/s[/tex]
So, the speed of the horse is 16 m/s.
it is also called solution
Explanation:
In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. ... The term "aqueous solution" is used when one of the solvents is water.
During ANY type of phase change, which of the following is TRUE? *
1. The temperature changes
2. The energy increases
3. The energy decreases
4. The temperature stays the same
What is a major problem with CFCs?
A-it is toxic to breathe.
B-It does not readily break down in the atmosphere.
C-It is a greenhouse gas.
D-It isn't a good refrigerant
Percentage of isotopes in 35/17 Cl and 37/17 Cl with the molar mass of chlorine as 35.5g and the mass of each nucleon to be 1.0000 amu
Answer:
The abundance of 35/17 Cl is 75% and 25% of 37/17Cl
Explanation:
The molar mass of an atom is defined as the sum of the masses of each isotope times its abundance, that is:
35.5amu = 35amu*X + 37amu*Y (1)
Where X is the abundance of the 35/17Cl and Y the abundance of 37/17 Cl
As there are just these 2 isotopes and the abundances of both isotopes = 1:
X + Y = 1 (2)
Replacing (2) in (1):
35.5 = 35X + 37(1-X)
35.5 = 35X + 37 - 37X
-1.5 = -2X
X = 0.75 = 75%
And Y = 100-75% = 25%
The abundance of 35/17 Cl is 75% and 25% of 37/17ClWithout the atmosphere, life on Earth would not be possible. Which of the following is NOT an explanation for how Earth’s atmosphere protects life on the planet?
A. It allows visible light to pass through completely.
B. It contains gases that filter out ultraviolet radiation.
C. It keeps Earth warm by trapping in heat.
D. It protects life from ultraviolet rays of light
Answer:
B
Explanation:
IM A CHEMISTRY WIZZZZ
:)
I hope u get full marks on your paper/test/quiz or whatever!
There is a 20 percent chance so stay positive!
Answer:
D
Explanation: ultraviolet rays are harmful to humans
type the correct answer in each box balance the equation
Answer:
5SiO2 + 2CaC2 ➡ 5Si + 2CaO + 4CO2
Explanation:
This question involves balancing the above equation. An equation is said to be BALANCED when all the atoms of each element in the reactant side equates that in the product side.
According to this question, a chemical reaction is given as follows: SiO2 + CaC2 = Si + CaO + CO2. Based on observation, the atoms of elements are Silicon, oxygen, calcium and carbon are not the same on the reactants and products side. Based on this, the balanced equation is:
5SiO2 + 2CaC2 ➡ 5Si + 2CaO + 4CO2
I really need help on this question! Thank you so much!
Answer:
A. Empirical formula => C₂H₄O
B. Molecular formula => C₄H₈O₂
Explanation:
From the question given above, the following data were obtained:
Mass of C = 0.273 g
Mass of H = 0.046 g
Mass of O = 0.182 g
Molar mass of compound = 88 g/mol
A. Determination of the empirical formula of the compound.
C = 0.273 g
H = 0.046 g
O = 0.182 g
Divide by their molar mass
C = 0.273 /12 = 0.023
H = 0.046 /1 = 0.046
O = 0.182 /16 = 0.011
Divide by the smallest
C = 0.023 / 0.011 = 2
H = 0.046 / 0.011 = 4
O = 0.011 / 0.011 = 1
Thus, the empirical formula of the compound is C₂H₄O
B. Determination of the molecular formula of the compound.
Empirical formula = C₂H₄O
Molar mass of compound = 88 g/mol
Molecular formula =?
Molecular formula = [C₂H₄O]ₙ
[C₂H₄O]ₙ = 88
[(12×2) + (4×1) + 16]n = 88
[24 + 4 + 16]n = 88
44n = 88
Divide both side by 44
n = 88 / 44
n = 2
Molecular formula = [C₂H₄O]ₙ
Molecular formula = [C₂H₄O]₂
Molecular formula = C₄H₈O₂
If N and O were to bond, the difference in electronegativity would be
and we would expect the bond to be
ionic, covalent)
Answer:
The bonds between nitrogen and oxygen are covalent bonds made from sharing electron pairs. The electronegativity of oxygen is 3.5.
describe a second degree burn
Answer:
Second-degree burns, or partial thickness burns, are more severe than first-degree burns. They affect the outer layer of skin, called the epidermis, and part of the second layer of skin, called the dermis. Second-degree burns can be very painful and often take several weeks to heal.
Explanation:
Human reproduction involves eggs, ovaries, sperm, and testes.
Which of these are gametes?
A eggs and sperm
B eggs and ovaries
C ovaries and testes
D sperm and testes
Answer:
A. Eggs and sperm
Explanation:
Genres are an organisms reproductive cells. Also referred to as sex cells. Females they are ova or egg cells, and males they are sperm.
How many grams of nitric acid, HNO3, are required to neutralize (completely react with) 4.30 g of Ca(OH)2?
Answer:
8.25 g HNO3 (please correct me if I'm wrong!)
The correct answer is 7.31 g HNO₃.
What is nitric acid used for?Nitric acid is used for the production of ammonium nitrate, a major component of fertilizers. It is also used for producing explosives like nitroglycerin and trinitrotoluene (TNT) and for oxidizing metals.
Please check the attached file for an explanation.
Learn more about nitric acid at
https://brainly.com/question/10082840
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What is the slope of the line?
Which is correct ? I’m really confused
Answer:
A. Florine has a stronger pull than Magnesium
Explanation:
Electronegativity refers to the tendency in which an tom would attract electrons to itself.
Below each element in the periodic table is their electronegativity value. Florine has the highest electronegativity value of 4.0.
Going through options;
A. Florine has a stronger pull than Magnesium
Florine = 4.0
Magnesium = 1.2
This correct
B. Hydrogen has a stronger pull than Phosphorus
Hydrogen = 2.1
Phosphorus = 2.1
This is wrong
C. Potassium has a stronger pull than Sodium
Potassium = 0.8
Sodium = 0.9
This is wrong
D. Iron has a stronger pull than Bromine
Iron = 1.8
Bromine = 2.8
This is wrong
respond if you got a min to help me with my problem
Answer:
I mean i dont know......
Explanation:
Help chemistry work!!!!!!!!
Answer:
SEE EXPLANATION
Explanation:
A)
1) The balanced chemical reaction is;
Fe2O3 + 3H2O------> 2Fe(OH)3
2) C12H22O11------> 12 C + 11H2O
B) 1 is a combination reaction
2 is a decomposition reaction
C) The molar mass of NH3 is 14 + 3(1) = 17 g/mol
Percentage composition of N = 14/17 * 100/1 = 82. 4 %
D) 1 mole of O2 contains 6.02 * 10^23 particles
E) For (NH4)3 PO4
We have 3(14 + 4(1)) + 31 + 4(16) = 149 g/mol
F) 1 mole of CaCO3 contains 100g of CaCO3
1.25 moles of CaCO3 contains 1.25 * 100/1 = 125 g of CaCO3
I'm having trouble balancing these. Can you help me
Answer:
Oh Okay
I hope u have a better rest of ur day
Can someone help me thx
Answer:
salt i know the answer and even sugar is
4 Al + 3 O2 -> 2 Al2O3 How much aluminum would be needed to completely react with 45 grams of Oz?
Answer:
50.6g Al would be needed
Explanation:
Based on the reaction:
4Al + 3O₂ → 2Al₂O₃
4 moles of aluminium react with 3 moles of oxygen to produce 2 moles of Al₂O₃
To solve this question we need to find the moles of 45g of O₂. Then using the chemical equation find the moles of Al and its mass:
Moles O₂ -Molar mass: 32g/mol-:
45g O₂ * (1mol / 32g) = 1.41 moles O₂
Moles Al:
1.41 moles O₂ * (4mol Al / 3mol O₂) = 1.875 moles Al
Mass Al -Molar mass: 26.98g/mol-:
1.875 moles Al * (26.98g / mol) =
50.6g Al would be needed
The amount of aluminum that would be required to completely react with 45 grams of O2 would be 50.59 grams.
From the balanced equation of the reaction:
[tex]4 Al + 3 O_2 ---> 2 Al_2O_3[/tex]
The mole ratio of Al to O2 is 4:3.
Mole of 45 grams of O2 = mass/molar mass
= 45/32
= 1.4063 moles
Equivalent mole of Al: 4 x 1.4063/3
= 1.875 moles
mass of Al = mole x molar mass
= 1.875 x 26.98
= 50.59 grams
More on stoichiometry calculations can be found here: https://brainly.com/question/22288091?referrer=searchResults
The value of resistance r was determined by measuring current I flowing through the resistance with an error
Correct question is;
Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurement of the current and the voltage difference are 3% each, then error in the value of resistance of the wire is?
Answer:
6%
Explanation:
From ohms law, we know that;
R = V/I
Where;
R is resistance
V is voltage
I is current
Now, the percentage error in the resistance is given by the formula;
ΔR/R = ΔV/V+ ΔI/I
We are told that the current and the voltage difference have a percentage error of 3% each. Thus;
ΔR/R = 3% + 3% = 6%
what is the conclusion that males are stronger than females
explain why it is more difficult to produce drinking water from waste water than from water in lakes
Answer:
Drinking water can be produced from waste water and from lakes but the difference is in the difficulty of producing water which we can consume.
Drinking water should be clean and toxic free so that if does not affect the human body. Waste water carry more toxic matter in comparison to lake water that's why, producing drinking water from waste water takes more time, expensive and difficult.
So, producing drinking water from waste water is more difficult as it require the removal of more toxic matter than water in lakes.
Which reactant (X) is missing from the equation shown?
X+ PO4 → H3PO4
Answer:
H
Explanation:
b/c the polyatomic PO4¯³
have 3 valance number
PLS ANSWER I WILL GIVE BRAINLY TO First!!!
Answer:
if I tell the ans u won't give me brainly
I really need help I'm not good with science
Answer:
A!!!!!!!!
Explanation:
Can someone please help me with this question.
Answer:
Birds evolved from a group of meat-eating dinosaurs called theropods. That's the same group that Tyrannosaurus rex belonged to, although birds evolved from small theropods, not huge ones like T. rex.
Answer:
we haven't done anything to study the roots of the bird yet
1. What is solar energy? Give an example
Answer:
Solar energy is energy from the sun. for example solar panels are used to use energy for the sun to give you eletricity.
Explanation:
Explanation:
solar energy is energy from the sun, it can be used for electricity.
Select the correct answer.
How many electrons does a covalent bond consist of?
A.
one
B.
two
C.
four
D.
eight
Explanation:
A covalent bond can be thought of as a 'shared pair' of electrons, so there are 2 electrons in each bond. That means that a double bond will have 4 electrons in the space between the bonded nuclei, and a triple bond will have 6.
MARK ME AS BRAINLISTwhat is the percent of just the oreo(out of 100%) from the total mass of these 3 cookies combined
Answer:
Percent mass of oreo = 35.11%
Explanation:
Given:
Mass of oreo = 17.1
Mass of 1st cookie = 16.2
Mass of 3rd cookie = 15.4
Find:
Percent mass of oreo
Computation:
Total mass = Mass of oreo + Mass of 1st cookie + Mass of 3rd cookie
Total mass = 17.1 + 16.2 + 15.4
Total mass = 48.7
Percent mass of oreo = [Mass of oreo/Total mass]100
Percent mass of oreo = [17.1 / 48.7]100
Percent mass of oreo = 35.11%
What does 10% humidity in a weather report indicate?
A)the level of humidity is high.
B)the level of humidity is low.
C)the level of humidity is moderate.
D)the air can not hold anymore water.
Answer:
B
the humidity is the % of water in the air and it is out of 100% of the air. so 10/100 is low
Answer:
B
Explanation:
30%-50% is considered moderate. Anything below 30% is considered dry, anything above 50% is considered high. I hope this helps!