Mass of ZnO added=1.765 g
Further explanation:Given
30gms of 10%ZnO(Zinc oxide)
15% ZnO
Required
mass of ZnO added
Solution
Amount of ZnO in 30 gms of 10% ZnO =3 gms
For 15% ZnO : x= ZnO added
New solution = 30+x = 15%, so the equation :
[tex]\tt \dfrac{3+x}{30+x}=15\%\\\\15\%(30+x)=3+x\\\\4.5+0.15x=3+x\\\\1.5=0.85x\\\\x=1.765~gms[/tex]
What percentage of Canada's 2005 population was between the ages of 30 and 44?
How many molecules are there in 560 grams of CoCl2?
Answer:
25.89 × 10²³ molecules
Explanation:
Given data:
Mass of CoCl₂ = 560 g
Number of molecules present = ?
Solution:
Number of moles of CoCl₂:
Number of moles = mass/molar mass
Number of moles = 560 g/ 129.84 g/mol
Number of moles = 4.3 mol
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
4.3 mol × 6.022 × 10²³ molecules /1 mol
25.89 × 10²³ molecules
last post as a troll lol, sorry but i need actual help this time.
Answer:
Lol
Explanation:
lol
nah
Which of the following is a simple definition of reduction?
A. the loss of electrons
B. the gain of electrons
C. an agent that oxidizes something
D. an agent that reduces something
The answer is B on Edg 2020
Answer:
B. the gain of electrons
Explanation:
An easy way to remember this concept is the pneumonic OIL RIG:
Oxidation is Loss (of electrons)
Reduction is Gain (of electrons)
What would the unit of measurement be for the density of a regular solid?
Answer:
SI unit: kg/m³
but g/cm³ is commonly used
Explanation:
Car battery energy that makes device work
Answer:
No it's not make device work
Explanation:
I think soo
Tetrachloromethane, CCl4 is produced from the substitution reaction between methane and chlorine gas. If the rate of formation of CCl4 is 0.05 mol dm^-3 min^-1, what is the rate of disappearance of chlorine gas?
The rate of disappearance of chlorine gas : 0.2 mol/dm³
Further explanationThe reaction rate (v) shows the change in the concentration of the substance (changes in addition to concentrations for reaction products or changes in concentration reduction for reactants) per unit time.
For reaction :
[tex]\tt aA+bB\rightarrow cC+dD[/tex]
The rate reaction :
[tex]\tt -\dfrac{1}{a}\dfrac{d[-A]}{dt}= -\dfrac{1}{b}\dfrac{d[-B]}{dt}=\dfrac{1}{c}\dfrac{d[C]}{dt}=\dfrac{1}{d}\dfrac{d[D]}{dt}[/tex]
Reaction for formation CCl₄ :
CH₄+4Cl₂⇒CCl₄+4HCl
From equation, rate of reaction = rate of formation CCl₄ = 0.05 mol/dm³
Rate of formation of CCl₄ = reaction rate x coefficient of CCCl₄
0.05 mol/dm³ = reaction rate x 1⇒reaction rate = 0.05 mol/dm³
The rate of disappearance of chlorine gas (Cl₂) :
Rate of disappearance of Cl₂ = reaction rate x coefficient of Cl₂
Rate of disappearance of Cl₂ = 0.05 x 4 = 0.2 mol/dm³
what are the 4 quantum numbers of Kr?
Answer:
2 8 18 8 those are the ones I believe.
Why does the Sun gravitationally dominate all other objects in the Solar System?
A balloon originally had a volume of 4.39 L at 44C and a pressure of 729 torr  to what temperature must the balloon be cooled to reduce its volume to 3.78 L of the new pressure is at 1.0 atm
The new temperature : 11.56 °C
Further explanationBoyle's law and Gay Lussac's law
[tex]\tt \dfrac{P_1.V_1}{T_1}=\dfrac{P_2.V_2}{T_2}[/tex]
P1 = initial gas pressure (N/m² or Pa)
V1 = initial gas volume (m³)
P2 = final gas pressure
V2 = final gas volume
T1 = initial gas temperature (K)
T2 = final gas temperature
V₁=4.39 L
T₁=44+273=317 K
P₁ = 729 torr = 0,959211 atm
V₂=3.78 L
P₂= 1 atm
[tex]\tt \dfrac{0.959211\times 4.39}{317}=\dfrac{1\times 3.78}{T_2}\\\\T_2=\dfrac{1\times 3.78\times 317}{0.959211\times 4.39}\\\\T_2=284.559~K=11.56~C[/tex]
When scientists conduct investigations, they collaborate to support each other's research. What is the importance of scientists repeating the same experiment using the same steps?
It creates further questions to investigate, which creates more accurate results.
Having several trials that produce the same results is more accurate.
When multiple scientists repeat investigations, it allows them to investigate errors.
When scientists get more accurate results, the observations can be compared.
Answer:
b or c but most likely it is c
Explanation:
B. I just did this not lying a few minutes ago LOL
GL on the rest of your test!!!! :D
Calcium hydroxide and hydrogen gas are produced by the reaction of calcium hydride and water
Explanation:
The reaction forms calcium hydroxide, Ca(OH)2 and hydrogen gas (H2). The calcium metal sinks in water and after an hour or so bubbles of hydrogen are evident, stuck to the surface of the metal.
Answer: B) calcium hydride + water -> calcium hydroxide + hydrogen
Explanation: B) on EDG
Which of these compounds has the highest boiling point?
Pentene
Chloropentane
2 Pentanone
Pentane
Answer:
2-Pentanone is the answer.
Explanation:
Carbon-14 has a half-life of 5715 years. It is used to determine the age of
ancient objects. If a sample today contains 0.060 mg of carbon-14, how much
carbon-14 will be present after 28,575?
The sample of Carbon-14 after 28,575 years=0.001875 mg
Further explanationGeneral formulas used in decay:
[tex]\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{T/t\frac{1}{2} }}}[/tex]
T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
Carbon-14 has a half-life of 5715 years, so t1/2=5715 years
A sample today contains 0.060 mg of carbon-14, so No=0.06 mg, then :
[tex]\tt Nt=0.06(\dfrac{1}{2})^{28575/5715}\\\\Nt=0.06(\dfrac{1}{2})^5\\\\Nt=0.001875~mg[/tex]
A chemical reaction occurs. The equation is: MgO ---> Mg + 0 This is a
combination reaction
decomposition reaction
double replacement reaction
single replacement reaction
Answer:
decomposition reaction
Explanation:
oxygen is broken down from magnesium oxide (mgo)
How many moles of nitrogen gas would be produced if 3.27 moles of copper(II) oxide were reacted with excess ammonia in the following chemical reaction? 2 NH3(g) + 3 CuO (s) – 3 Cu(s) + N2(g) + 3 H2O(g)
Moles of Nitrogen(N₂) gas would be produced : 1.09
Further explanationThe reaction coefficient in a chemical equation shows the mole ratio of the components of the reactants and products
If one mole of the reactant or product is known, then we can determine the moles of the other compounds involved in the reaction
Reaction
2NH₃(g) + 3CuO (s) ⇒ 3Cu(s) + N₂(g) + 3 H₂O(g)
Copper(II) oxide was reacted with excess Ammonia, so CuO as a limiting reactant and moles of the product is based on moles of CuO
moles of CuO = 3.27
From the equation, the mol ratio of CuO : mol N₂ = 3 : 1, so mol N₂ :
[tex]\tt \dfrac{1}{3}\times 3.27=1.09[/tex]
Match the part of the wave to its description.
Crest
Wavelength
Trough
Amplitude
These are the correct answer your welcome ;)
Answer:
sgsgueiehéyegeysuegeteue2
Answer:
Explanation:
The answers you put are correct...
crest- A crest point on a wave is the maximum value of upward displacement within a cycle. A crest is a point on a surface wave where the displacement of the medium is at a maximum.
wavelength- In physics, the wavelength is the spatial period of a periodic wave the distance over which the wave's shape repeats. (how long the wave is)
trough- A trough is the opposite of a crest, so the minimum or lowest point in a cycle.
amplitude- Amplitude, in physics, the maximum displacement or distance moved by a point on a vibrating body or wave measured from its equilibrium position. It is equal to one-half the length of the vibration path. ... Waves are generated by vibrating sources, their amplitude being proportional to the amplitude of the source.
Hope this helps! Have a great day!! :D
The_______ and _____ are the main systems that move fluid throughout the body.
Answer:
circulatory system, lymphatic system
Explanation:
I just did the assigment and got it right.
Phosphorus-32 has a half life of 14.3 days. How many days will it take for a
radioactive sample to decay to one-eighth its original size?
It will take 42.9 days
Further explanationGeneral formulas used in decay:
[tex]\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{T/t\frac{1}{2} }}}[/tex]
T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
t1/2=14.3 days
Nt/No=1/8
[tex]\tt Nt=No(\dfrac{1}{2})^{T/t1/2}\\\\\dfrac{Nt}{No}=\dfrac{1}{2}^{T/t1/2}\\\\\dfrac{1}{8}=\dfrac{1}{2}^{T/t1/2}\\\\(\dfrac{1}{2})^3=\dfrac{1}{2}^{T/t1/2}\\\\3=T/14.3\rightarrow T=42.9~days[/tex]
Please help. Im not a very smart person
The nucleus is the cell as
A nucleus is an organelle found in the eukaryotic cells. Inside it's fully enclosed nuclear membrane, it contains the minority of the cell's genetic material. This material would be called DNA molecules.
Hope this helps! If not I'm so sorry. Have a lovely day
What is the element Ar classified as in the periodic table?
a noble gas
a halogen
a metalloid
a metal
The element Ar classified as noble gas in the periodic table. Therefore, the correct option is option A.
What is noble gas?The noble gases are a group of chemical elements that share several characteristics. They are all monatomic, odourless, and colourless gases with relatively little chemical reactivity under normal conditions. Oganesson (Og) is a highly radioactive element created synthetically.
Although the IUPAC has included oganesson since "group 18" and "noble gas" have been used interchangeably, oganesson may not be appreciably chemically noble and therefore is projected to deviate from the norm and just be reactive owing to relativistic effects. Its chemistry is still being studied due to the exceptionally short 0.7 ms ½ of its sole known isotope. The element Ar classified as noble gas in the periodic table.
Therefore, the correct option is option A.
To know more about noble gas, here:
https://brainly.com/question/7036466
#SPJ7
1.Outline the results of the Cathode ray tube?
Answer:
this showed that the cathode rays traveled in straight line
How much heat is required to boil 78.5 gg of water at its boiling point?
Answer:
206 kj of heat is required to boil 78.5 kg of water at its boiling point
pls help 40 points!! Augie created this chart about the two kinds of waves.
A 2-column table with 3 rows titled 2 Kinds of Waves. The first column labeled Title 1 has entries the transfer energy is perpendicular to the direction of the wave motion, particles move up and down, particles move only slightly. The second column labeled Title 2 has entries the transfer direction is parallel to the direction of wave motion, particles move side to side, particles move only slightly.
Which best labels the chart?
Title 1 is “Longitudinal Waves,” and Title 2 is “Transverse Waves.”
Title 1 is “Transverse Waves,” and T
its b
i did the quiz and got it right it is b
Answer:
b
Explanation:
took test on edge
Silver nitrate and magnesium chloride react according to the following equation:
2AgNO3(aq) + MgCl2(aq) — 2AgCl(s) + Mg(NO3)2(aq)
What volume (in ml) of 0.247M MgCl2(aq) is required to react with 63.2 mL of 0.192M AgNO3(aq)?
Answer:
V=24,3mL
Explanation:
1)n(AgNO3)=Cm*V=0.063l*0.192M=0.012
2)n(AgNO3)/2=n(MgCl2) => MgCl2=0.012/2=0.006
3)V(MgCl2)=n/Cm=0.006/0.247=0.0243L=24,3ml
Jean's mother lit a candle and placed it on his birthday cake. As they sang happy birthday, the wick burned, the wax
melted, the candle changed shape, and the air around the candle heated up. Which of the following is NOT an
example of a physical change?
Answer:
The wick burning
Explanation:
If 4.25 grams of copper were plated out in the reaction:
3Cu2+ + 2Al ---> 3Cu + 2Al3+
What mass of aluminum would have dissolved?
Please show all work!
Answer:
gravwfewtu
Explanation:
ushifelllf
Two ways water and ice are the same
Answer:
1- water is ice
2- ice is water
Explanation:
1- the water is just froze
2- the ice is just solid water
an apple with a mass of 0.95 kilograms hangs from a tree branch 3.0 meters above the ground. what is the potential energy of the apple?
0.28j
2.8j
28j
280j
Answer:
285 JExplanation:
The potential energy of a body can be found by using the formula
PE = mgh
where
m is the mass
h is the height
g is the acceleration due to gravity which is 10 m/s²
From the question we have
PE = 0.95 × 10 × 30
We have the final answer as
285 JHope this helps you