Answer:
1) 3Fe + 2O(2, this is the subscript) - Fe(3)O(4)
2) 2Sr + O(2) - 2SrO
3) Sn + 2NaOH - Na(2)SnO(2) + H(2)
4) 2K + Br(2) -2KBr
5) 2C(8)H(18) + 25O(2) - 16CO(2) + 18H(2)O
1. True or False? The scientific method is defined as a method of research
in which a problem is identified, data is gathered, and a hypothesis is
created based off the data, then the hypothesis is tested.
Answer:
true
Explanation:
please mark BRAINLIEST
The millions of fossils that scientists have collected are called the fossil __.
Answer:
record
Explanation:
Which option is an example of a chemical property?
A. boiling point
B. ability to react with oxygen
C. color
D. density
Answer:
boiling point
Explanation:
Option B
IUPAC name for C3H7
Answer:
propyl
Explanation:
......:)
..;) .........
Sodium + oxygen
What colour is the flame produces
Answer:
Orange
Explanation:
I used google my b
Answer:
ORANGE
explanation:
Small pieces of sodium burn in air with often little more than an orange glow. Using larger amounts of sodium or burning it in oxygen gives a strong orange flame.
With some manipulation, the Rydberg equation can be rewritten in the form
E=constant×(1nf2−1ni2)
which allows you to calculate the energy of the emitted light. Express this constant in terms of the constants h, c, and RH using relationships between wavelength and energy as well as the Rydberg equation from the introduction.
Express the constant in terms of h and c, and RH.
Please help me with this question?
Answer:
attached below is the detailed solution
answer : value of constant = 2.18 * 10^-18 J
Explanation:
Express the constant in terms of h and c and RH
attached below is the detailed solution
Constant = [tex]h_{C} R_{H}[/tex]
= ( 6.626 * 10^-34 ) * ( 3 * 10^8 ) * ( 1.097 * 10^7 )
= 2.18 * 10^-18 J
The Planck equation and the light speed allow us to find the results for the transformation of the Rydberg equation are:
[tex]E = A ( \frac{1}{n_1^2}\frac{x}{y} - \frac{1}{n_2^2} )\\A= R_H \ h \ c \\A = 2.18 \ 10^{-18} j[/tex]
The Rydberg equation is an empirical expression that explains the wavelength of the emissions.
[tex]\frac{1}{\lambda } = R_H ( \frac{1}{n_1^2} - \frac{1}{n_2^2} )[/tex]
Where λ is the wavelength of the emitted radiation, is the Rydberg constant, n₁ and n₂ are integers with n₁ <n₂
It is asked to write the Rydberg equation for the energy.
Let's use the Planck relation.
E = h f
The light speed is related to the wavelength and frequency of radiation.
c = λ f
Where E is the energy, h the Planck constant, c the speed of light, λ the wavelength and f the frequency.
Let's substitute.
E = [tex]\frac{hc}{\lambda}[/tex]
[tex]\frac{1}{\lambda} = \frac{E}{hc}[/tex]
Let's substitute in the Rydberg equation.
[tex]\frac{E}{hc} = R_H ( \frac{1}{n_1^2} - \frac{1}{n_2^2}) \\E = R_H \ h \ c \ ( \frac{1}{n_1^2} - \frac{1}{n_2^2} )[/tex]
We can write is an constant of the form.
A = [tex]R_H h c[/tex]
The value of the constant is :
A = 1,097 10⁷ 6,626 10⁻³⁴ 3 10⁸
A = 2.18 10⁻¹⁸ J
In conclusion, using the Planck equation and the light speed we can find the results for the transformation of the Rydberg equation are
[tex]E = A ( \frac{1}{n_1^2} - \frac{1}{n_2^2} )\\ A = R_H h c\\[/tex]
A = 2.18 10⁻¹⁸ J
Learn more here: brainly.com/question/14691724
I hate chemistry please help
Answer:
Love it because Love it
Explanation:
The momentum of a 23 000 kg truck traveling eastward with a velocity of 50.0 m/s is kom/s
Answer:
Explanation:
I'm not sure what you mean by the units. The answer using kg and ms is 23000 * 50 = 1150000 kg m/s
which of these elements is most likely to be magnesium the most metallic of all samples?
Answer:
B
Explanation:
Just did it on usa test prep
The element which is most likely to be magnesium is the element with the electronic configuration same as magnesium.
What is an element?It is defined as a substance which cannot be broken down further into any other substance. Each element is made up of its own type of atom. Due to this reason all elements are different from one another.
Elements can be classified as metals and non-metals. Metals are shiny and conduct electricity and are all solids at room temperature except mercury. Non-metals do not conduct electricity and are mostly gases at room temperature except carbon and sulfur.
The number of protons in the nucleus is the defining property of an element and is related to the atomic number.All atoms with same atomic number are atoms of same element.
Learn more about element,here:
https://brainly.com/question/14347616
#SPJ6
Which describes the motion of the car as shown by the graph?
A) travels at a constant speed
B) not moving
C) changing directions
D) speeding up
Burning is a type of_________reaction.
O replacement
O decomposition
O synthesis
O combustion
Answer:
Combustion
Explanation:
Happy Halloween!
(b) Define, in terms of oxidation state, the Oxidizing agent
a substance which gains oxygen
a substance whis lose hydrogen
a substance which experiences a decrease in oxidation state
a substance which experiences an increase in oxidation state
Answer: a substance whis lose hydrogen
Explanation:
Which ecosystem is the least stable?
Answer:
tundra bc it has barley any food source and has vary little inhabitants
Explanation:
Answer:
a patch of lichens on bare rock
• True False estion 2 (1 point) Water and ice are made from the same molecule H2O True False
Answer:
true i think
Explanation:
I’ll give the Brainliest, you also need to explain how the answer you got is correct.
Choose the best description of a neap tide.
A. Neap tides produce during the highest tides of the month.
B. Neap tides happen during winter and summer.
C. Neap tides could be described as low high tides and high low tides.
D. A neap tide is the period halfway between tides when the tide changes direction.
Thank you!
Answer:
D. A neap tide is the period halfway between tides when the tide changes direction. (correction) Answer : C
Explanation:
Process of elimination can be used. First off, A is incorrect because neap tides have the smallest tidal range ; spring tides would fit this choice. B is incorrect since neap tides are specific to the first, and third quarter moons when the sun and moon are right angles. C is wrong because it is the other way around since high tides are a little higher than average and low tides are a little lower than average (correction) this is correct since higher low tides and lower high tides are closer together and have a smaller tidal range than standard tides(spring tides) with higher high tides, and lower low tides. D is correct because they occur halfway between the spring tides (correction): incorrect since a neap tides occur around a week(7 days) after a spring tide(moderate tides). There is no evidence this is true.
There are three patterns: diurnal(one high and low tides a day), semidiurnal(two high and low tides a day), and mixed(two high and low tides a day of different lengths).
The spring and neap tides are the types of tides involved with the low and high tides.
Select the correct answer
Which statement best supports the idea that water conservation is important for human societies?
OA Once humans use water, it cannot be reused ever again,
OB. Only about 1% of the freshwater on Earth is easily accessible.
OC Water is constantly being lost from the hydrosphere
OD. Most land animals use salt water instead of freshwater.
Answer:
Only about 1% of the freshwater on Earth is easily accessible.
Explanation:
Freshwater accounts for a minimal proportion of water resources on planet earth. About 70 percent of the world surface area is covered by water, but only about 2.5 percent of this mass of water is fresh. The remaining are marine or salt water. Amazingly, just about 1 percent of this freshwater is easily accessible. The other 1.5% is trapped in glaciers and snowfields.
This underscore the need for water conservation on the planet since fresh water is a scarce resource and people living in many areas have no access to fresh water.
Select the correct answer.
In which situation is no work considered to be done by a force?
A.
when the angle between the force and displacement is 180°
B.
when the angle between the force and displacement is 90°
C.
when the angle between the force and displacement is 45°
D.
when the angle between the force and displacement is 0°
Answer:
Explanation:
when the angle between the force and displacement is 0
PE = mgh, solve for m
Answer:
P.E. = mgh, where m is the mass in kilograms,
Answer:
[tex]m = \frac{PE}{gh} [/tex]
Explanation:
[tex]if \: PE = mgh \\ then \to \\ m = \frac{PE}{gh} [/tex]
♨Rage♨
CAN SOMEONE HELP ME!!!!!!!!!!!!!
Answer:
5 g/cm^3
Explanation:
Density = mass / volume
Using the formula M=dx v, Calculate the mass of a liquid with a density of
17.5 g/mL and a volume of 7mL.
Answer:
The answer is 122.5 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question
volume = 7 mL
density = 17.5 g/mL
We have
mass = 17.5 × 7
We have the final answer as
122.5 gHope this helps you
A substance absorbed 895 J and caused its temperature to increase by 10 ºC. If the substance has a mass of 27.9 g, what is the substance's specific heat in J/(gºC) ?
1.) 3.21
2.) 4.62
3.) 1,406.25
4.) 249,705
Answer:
i dont get the equation sorry wish i can help
Explain why warm air temperature has lower air pressure than cold air?
Answer:
Differences in temperature cause differences in air density. Warmer air is less dense than cold, which is why warm air tends to rise and cold air sinks.
temparature affects particles. warm particles are more spread out.
Explanation:
. Being acted on by gravity, colder, denser air weighs more and exerts greater pressure per unit area.
Identify the law that explains the following observation:
Nitrogen Dioxide can be formed by reacting 14 grams of
nitrogen with 32 grams of oxygen.
Answer:
Proust's law of definite proportion
Explanation:
The law of constant proportion states that the components elements of a given chemical compound combine with each other in a fixed mass ratio when the compound is produced by any given process
Therefore, from the question, the chemical formula for Nitrogen Dioxide is NO₂, where the molar mass of nitrogen, N = 14
The molar mass of oxygen, O = 16
Given that one molecule of NO₂, contains one atom of nitrogen and two atoms of oxygen, one mole of NO₂ will contain 14 grams of nitrogen and 32 grams of oxygen, according to Proust's law of definite proportion.
need help asap
Calculate the frequency for a wavelength of 635 nm.
Answer:
472114107.086614 MHz
Explanation:
f = C/λ
λ: Wavelength in meters
C: Speed of Light (299,792,458 m/s)
what is the concept of the doppler effect?
In a longitudinal wave, particle displacement is
from google, so I think the answer to that question is the second one
Sugar is added to iced tea and the contents are stirred until all of the sugar dissolves. How would the tea now be classified?
What is involved in weathering?
Answer:
the answer is water.Hope this helps
A metal block, 2.0cm x 2.5cm x 3.0cm, has a mass of 40.5g. What is the density of the sample? What type of metal is the metal block composed of?
Aluminum - 2.699
Copper - 8.92
Iron - 7.874
Lead - 11.43
Nickel - 8.908
Tin - 7.265
Zinc - 7.14
Answer:
The block is made up of aluminum.
density = 2.7 g/cm³
Explanation:
Given data:
Dimension of metal block = 2.0 cm×2.5 cm× 3.0 cm
Mass of block = 40.05 g
Density of block = ?
Which metal is this = ?
Solution:
Density:
Density is equal to the mass of substance divided by its volume.
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Volume of block = 2.0 cm×2.5 cm× 3.0 cm = 15 cm³
d = m/v
d = 40.5 g/ 15 cm³
d = 2.7 g/cm³
The block is made up of aluminum.
HELPPP PLEASEEE!!! calculate the energy of radiation with a wavelength of 432 nm