Answer:
454
Explanation:
j
What happens in nuclear fusion?
A. Isotopes are made from gamma rays.
B. Two separate nuclei form one nucleus.
C. Missing mass is added back to a nucleus.
D. Nuclei spontaneously break down.
I need help with both of the questions fast plz!!!
Answer: SMALLEST is lithium
LARGEST is Fluorine
Explanation:
Bacteria and mold break down fallen leaves on the forest floor. When they do
this, they release carbon dioxide into the atmosphere and ntrogen to the
soil. Which of the following roles do bacteria and mold have in the
environment?
Answer:
H
Explanation:
not sure tho sorry if I'm wrong
summarize what you know about carbon
Answer:
Carbon is a chemical element, like hydrogen, oxygen, lead or any of the others in the periodic table. Carbon is a very abundant element. It exists in pure or nearly pure forms – such as diamonds and graphite – but can also combine with other elements to form molecules.
What percentage of the total atomic mass of magnesium bromide (MgBr2) is composed of bromine? Hint - consider the mass of both atoms of bromine in your calculation. A.43% B.87% C.13% D.63%
Answer:
B. 87%
Explanation:
First, we calculate the molecular mass of magnesium bromide (MgBr2) as follows;
MgBr2 = 24.3 + 79.9(2)
= 184.1g/mol
Since 1 atom of bromine contains 79.9g, then the mass of two atoms of bromine (Br2) is 79.9 × 2 = 159.8g
Hence, the percentage of bromine (Br2) in MgBr2 is calculated as follows:
% mass of Br2 = mass of Br2/ molecular mass of MgBr2 × 100
% mass of bromine = 159.8/184.1 × 100
% mass of bromine = 0.8680 × 100
% mass of bromine = 86.8%
Approximately, % mass of bromine is 87%
Which pure substance can be classified as an element?
Answer:
A substance that cannot be broken down into chemically simpler components is an element.
Aluminum, which is used in soda cans, is an element.
Charles's law describes the relationship of the volume and temperature of
gas at a constant mass and pressure. According to this law, what would
happen to the temperature of the gas if its volume decreased from 1.0 L to
0.50 L?
O A. The temperature would decrease by 500 K.
O B. The temperature would double.
O C. The temperature would be reduced by half.
O D. The temperature would increase from 500 K to 1000 K.
Answer:
The temperature would be reduced by half
Explanation:
Charles' Law => V ∝ T => V = kT => k = V/T
For two sets of T vs V conditions, the system constant (k) remains unchanged and k₁ = k₂ => V₁/T₁ = V₂/T₂.
Therefore, if V₁ is reduced to 1/2V₁ = V₂ => V₁/T₁ = 1/2V₁/T₂ => V₁/T₁ = V₁/2T₂
and solving for T₂ => 1/T₁ = 1/2T₂ => 2T₂ = T₁ => T₂ = 1/2T₁
∴ The initial temperature (T₁) would be reduced by half or, T₂ = 1/2T₁
PLEASE HELP PLS LFHLFATOI;RHG
Answer:
C. A model of a water molecule
Explanation:
H20, model shows 2 H,s (H2) and 1 O (O) which makes H2O. It's a model and not a real life picture of a molecule.
Answer:
C. A model of a water moleculeExplanation:
2 hydrogen + Oxygen= water molecule#CarryOnLearning
[tex]{.hope (it helps}}) [/tex]
All molecules have London forces between them, but dipole-dipole and hydrogen bonding are so much stronger that when they are present we
can ignore London forces. Only NONPOLAR molecules will SHOW LDF. Which of these has ONLY LDFs?
A. I2
B. HF
C. NH3
D.H2S
Answer:
a
Explanation:
khan academy
Among the options given, only [tex]I_2[/tex] shows London-Dispersion forces. Thus, the correct option for this question is A.
What is the London-Dispersion force?The London-Dispersion force may be defined as a type of provisional attractive force that arises when the electrons in two adjacent atoms tenanted positions that construct the atoms to form temporary dipoles. It is considered the weakest intermolecular force.
[tex]H_2S[/tex] shows dipole-dipole interactions because hydrogen and sulfur have huge electronegative differences. Due to this, their bonds are polar. [tex]NH_3[/tex] shows hydrogen bonding between them. HF shows dipole-dipole interactions because it is a polar covalent molecule.
Therefore, only [tex]I_2[/tex] shows London-Dispersion forces. Thus, the correct option for this question is A.
To learn more about Hydrogen bonding, refer to the link:
https://brainly.com/question/1420470
#SPJ2
What does it mean if an element has 8 valence electrons?
Answer:
the answer is the D, it has a full octet
What is the amount of sodium hydroxide, NaOH, in 4.6 g? Use the values given for
the atomic mass of Na, H, and O.
6
Na = 22.989 770 u
H = 1.007 94u
0 = 15.99944
9
a) 0.19 mol
12
b) 0.12 mol
15
c) 1.8 x 102 mol
d) 0.20 mol
Answer: 0.12 Mol
Explanation: Molecular mass of NaOH is = 39,997 g/mol which is Atomic mass of Na + Atomic Mass of H + Atomic mass of O
4.6g / 39.997g/mol = 0.12 mol
What is the number of carbon atoms in a cycloalkyne with 8 hydrogen atoms
Answer:
4
Explanation:
C4H8
types of radioactive nuclide
Answer:
On Earth, naturally occurring radionuclides fall into three categories: primordial radionuclides, secondary radionuclides, and cosmogenic radionuclides. Radionuclides are produced in stellar nucleosynthesis and supernova explosions along with stable nuclides.
Is hand washing a chemicals change or physicals change and why?
Answer:
If you wash your hands with soap, the soap molecules act as a link between the water you're washing with and the oil on your skin.
Explanation:
energy the ability to do ____ or cause ____ its measured in _____ and is found in many different _____. energy can be classified as _____ or _____ energy
PLS HELP QUICK!!!!!
Which sequence represents a portion of a
homologous series of hydrocarbons?
1.
C2H2, C2H4, C2H6
2.
C2H2, C3H4, C6H6
3.
C2H4, C3H4, C4H4
4.
C2H4, C3H6, C4H8
Answer:
4. C2H4, C3H6, C4H8
this is the alkane homologous series of hydrocarbons.
Their general formula is CnH2n
you can check this fits for all these compounds
put n = 1, 2, 3 and so on
Why does water appear blue?
A. Because the sky is reflecting on the water
B. Because of the way the water molecules are moving
C. Because of blue-colored elements dissolved in the water
Las levaduras son microorganismos usados en la industria alimentaria en diversos procesos, uno de ellos es la fermentación del azúcar para producir alcohol, tal como se representa en el esquema. LEVADURA + AZÚCAR + CALOR ⇒ Dióxido de carbono + alcohol ¿Por qué este proceso se considera una reacción química? *
Porque solamente hay un aumento de temperatura.
Porque el azúcar cambia de estado.
Porque el azúcar se transforma en otra sustancia.
Porque el alcohol se evapora rápidamente.
Respuesta:
Porque el azúcar se transforma en otra sustancia.
Explicación:
Consideremos el cambio representado en el siguiente esquema.
LEVADURA + AZÚCAR + CALOR ⇒ Dióxido de carbono + alcohol
¿Por qué este proceso se considera una reacción química?
Porque solamente hay un aumento de temperatura. NO. El aumento de temperatura no indica una reacción química. Porque el azúcar cambia de estado. NO. El azúcar no cambia de estado. Porque el azúcar se transforma en otra sustancia. SI. En una reacción química, unas sustancias (reactivos) se transforman en otras (productos). Porque el alcohol se evapora rápidamente. NO. La evaporación es un cambio físico.2500 cal of heat are absorbed by 150 grams of water that is initially at 23°C, what is the final temperature of the water?
Answer:
H=MC∆T
Heat = Heat absorbed or given off
M=Mass
C=Specific Heat Capacity of substance (Water in thus case). It has a Specific Heat capacity of 4200J/kg.k
∆T= Temp Change (T2-T1)
I'll solve with My Heat in Joules.
The heat is given in Calorie
1Cal = 4.186J
2500cal = 10,465J.
∆T= H/MC
=10465/0.15(4200)
=16.6°C
∆T=16.6
T2 - T1 = 16.6
T2 = 16.6+T1
T2 = 16.6 + 23
T2 = 39.6
Approx. 40°C
What is the total mass of a 10 gram sample of 42K that will
remain unchanged after 12.4 hours?
A 2.5 g
B 5.0g
C 7.5 g
D 10 g
True or False: Electrons are significantly smaller than protons and neutrons, we can ignore electrons when we consider the physical property of an atom.
Answer:
true
Explanation:
Question 21
Which equation is a balanced chemical equation?
A
2NaOH + CaBr2 + Ca(OH)2 + NaBr
B
NO + Cl2 → NOCI
с
CaCO3 + CaO + 2CO2
D
2AlCl3 + 3Mg + 3MgCl2 + 2A|
D
B
Ос
ОА
Answer:
the equation is not correctly written but the answer is option D
The balanced equation among the given options is D, where each of the elements are equal in number on both side.
What is balanced reaction?A balanced chemical equation for a reaction represents perfect stoichiometric ratios of each reactants and products. Each elements have to be equal in number on both sides.
The number of elements or groups can be balanced each side by multiplying with suitable integers. The chemical equation in D is balanced where, Al, Cl and Mg are balanced on both side.
The equation in A, is not balanced where, number of Na and Br are not balanced. In equation B Cl is two in reactant side and one in product side. Thus, not balanced. Similarly in option C, oxygen and calcium are not balanced. Therefore, option D is correct.
To find more on balanced reactions, refer here:
https://brainly.com/question/14258973
#SPJ2
Explain the steps needed to obtain an ammonium salt
Answer:
When an amine is added to a solution of a strong acid, such as hydrochloric acid, the amine nitrogen atom is protonated to produce an ammonium salt. Ammonium salts of low molecular weight are soluble in water if the hydrocarbon portion of the amine is small.Ammonium cation is found in a variety of salts such as ammonium carbonate, ammonium chloride and ammonium nitrate. Most simple ammonium salts are very soluble in water. An exception is ammonium hexachloroplatinate, the formation of which was once used as a test for ammonium.
Calcular el porcentaje de cada elemento en los compuestos químicos dados.
1. KNO3 (Nitrato de potasio: fertilizante): %K=? , %N=? , %O=?
Answer:
%K=38,6% %N=13,86% %O=47,54%
Explanation:
%K=M K/M KNO3
=39/101
=38,6%
%N=14/101
=13.86%
%O=100%-%K-%N
=100-38,6-13,86
=47,54%
A stretched spring has an elastic potential energy of 35 J when it is stretched 0.54 m. What is the spring constant of the spring? Round your answer to two significant figures.
StartFraction N over m EndFraction
Answer:
240 N/m
Explanation:
Using the formula as follows:
U = ½kx²
Where;
U = elastic potential energy (J)
K = spring constant (N/m)
x = stretched displacement (m)
According to the information provided in this question,
U = 35J
x = 0.54m
k = ?
U = ½kx²
35 = ½ × k × 0.54²
35 = ½ × k × 0.2916
35 = 0.2916k/2
70 = 0.2916k
k = 70 ÷ 0.2916
k = 240.05
To 2s.f, the spring constant (k) = 240 N/m.
Answer: 240
Explanation:
An inflated balloon contains X air molecules.After some time the volume of the balloon is found to be the half at the same temperature and pressure when a few air molecules are expelled out. a)How many molecules will be there in the balloon now? b) Which is the gas law associated with this?
Answer:
See explanation
Explanation:
According to Avogadro's law, the volume of a given mass of gas is directly proportional to the number of molecules of gas present at constant temperature and pressure.
Hence; V1/n1 = V2/n2
The implication of this is, if there were X molecules present and the volume of the balloon is halved, the number of molecules of gas present is also halved. So, we now have X/2 number of gas molecules present in the balloon.
This is in accordance with the statement of Avogadro's law.
How many moles of Mercury ll oxide are needed to produce 125g of o2
The table below gives some characteristics of element Y
what is the identity of Y
Answer:
I doint understand that question resend it again
9. The prefix oct- means
That there are
8 hydrogen atoms
8 carbon atoms
8 single bonds
8 double bonds
Answer:
2nd option
Explanation:
it means that there are 8 carbons
The prefix oct- mean that there are 8 carbon atoms. Therefore, option (B) is correct.
What are the steps for the IUPAC nomenclature?The 1st step for the IUPAC nomenclature of a compound is to select the longest, most substituted carbon chain with a functional group. Then the use of the primary suffix indicates the degree of unsaturation such as 'ane' or 'ene.
Then the identification of the secondary suffix indicates the number of functional groups in the molecule and the number of times of the same functional group such as di, tri, tetra, etc.
The prefix can be used to indicate the side chains, substituents, and low-priority functional groups. The prefix Oct- is used if there are eight carbon atoms in the chain. The prefix 'ane' is used for single bonds and the prefix 'ene' is used for the double bonds in the carbon chain.
Learn more about IUPAC nomenclature, here:
brainly.com/question/2599286
#SPJ6
Which characteristic of water allows its molecules to form hydrogen bonds? (1 point)
Answer:
Water molecule is polar.
Explanation:
The partial negative charge on the O of one molecule can form a hydrogen bond with the partial positive charge on the hydrogens of other molecules.