Answer:
Shielding effect is the decrease in the attractive force of the nucleus on tge valence electrons due to inner shell electrons. ... Shielding effect remains same across a period, that is because the number of shells are same for each element in a period. hope this helps!
1. The chemical formula of caffeine is C8H10N4O2. Determine the percent composition of the molecule.
Show work please
Answer:
we find the mass for each element in one mole by multiplying the number of atoms in one molecule with the atomic mass
mC=8Ac=8*12=96g
mH=10AH=10*1=10g
mN=4AN=4*14=56g
mO=2AO=2*16=32g
by adding the masses together we find the molar mass of the molecule
M=mC+nH+mN+mO=96+10+56+32=194g/mole
we apply the rule of threes to find the percentage of each element
194g..96gC..10gH...56gN....32gO
100g....a...........b...........c.............d
a=(100*96)/194=49.48%C
b=(100*10)/194=5.19%H
c=(100*56)/194=28.85%N
d=(100*32)/194=16.48%O
Explanation:
complete the bolded items in each box below
Show the bolded items and the boxes.
How do we know if molecules have kinetic energy?
Identify the product of the hydrogenation of the following alkene: CH3 + H2 → A) OH B) CH3 CH3 C) Колата jo sono ue D)
4. Proteins make up our bodies ?
how many significant figures are in the measurement 12.4 kg
Equal masses of two substances absorb the same amount of heat. The temperature of a substance A increases twice as much as substance B. Which substance has a higher specific heat capacity?
A. Substance A
B. Substance B
Letter A because the temperature of a substance A increases "Twice as much".
Gas in a balloon occupies 3.3 liters. What volume will it occupy if the pressure is changed from 100 kPa to 90.0 kPa, if the temperature is held constant?
Answer:
3.7 L
Explanation:
Initial volume (V₁) = 3.3 L
Initial pressure (P₁) = 100 KPa
Final pressure (P₂) = 90 KPa
Final volume (V₂) =?
The final volume of the gas can be obtained by using the Boyle's law equation as follow:
P₁V₁ = P₂V₂
100 × 3.3 = 90 × V₂
330 = 90 × V₂
Divide both side by 90
V₂ = 330 / 90
V₂ = 3.7 L
Thus, the final volume of the gas is 3.7 L
Living organisms contain a variety of specailsed cells name one example of a specialised cell in the body and state its function example : function :
Answer:
See the answer below
Explanation:
The cell represents the basic unit of life and any living organism.
One example of specialized cells in the body are the sex cells.
The sex cells are primarily concerned with reproduction and perpetuation of life. The cells undergo meiosis to produce haploid gametes. Male and female gametes then fuse together during fertilization to give rise to diploid zygotes which eventually give rise to new organisms.
what is phase change?
Explanation:
In chemistry, thermodynamics, and many other related fields, phase transitions (or phase changes) are the physical processes of transition between the basic states of matter: solid, liquid, and gas, as well as plasma in rare cases.
Answer:
In chemistry, thermodynamics, and many other related fields, phase transitions are the physical processes of transition between the basic states of matter: solid, liquid, and gas, as well as plasma in rare cases. A phase of a thermodynamic system and the states of matter have uniform physical properties.
Explanation:
Am I doing this right?
What is [OH-] of a solution
with a pH of 4.0?
Answer in M
Why does nobody fking answer my questions.
How did stromatolites contribute oxygen to the early atmosphere?
through methane degradation
through photolysis
by weathering of rocks
through photosynthesis
Answer:
by wearing of rocks
Explanation:
earths gravity your welcome
Answer:
weathering of rocks is the answer to your question
Which of the following elements is the most reactive?
A. Ba
B. Cs
C. Hf
D. Lu
Answer: Cs because its further to the right on the table, meaning its more reactive.
Explanation:
Answer:
Cs
Explanation:
This element is the farthest right, and lowest meaning that its reactivity is very high.
1. valence electrons and electronegativity
2. Both reactivity and electronegativity decrease down a group.
3. Electronegativity decreases down a group and reactivity increases down a group.
4. The number of valence electrons increases from left to right.
5. Cs
{quizlet: captncrun}
1. All the individuals of one type of clownfish ( e. species) living in a reef compose which level of organization?
When electrons lost a blank ion is formed
When electrons are gained a blank ion is formed
Answer:
I love it
Explanation:
☁️ Answer ☁️
annyeonghaseyo!
Your answer is:
When electrons are lost, a positively charged ion is formed. When electrons are gained, a negatively charged ion is formed. (I like the car)
Hope it helps.
Have a nice day noona/hyung!~ ￣▽￣❤️
The number of ions produced when a substance dissolves is always equal to the number of Adams in a chemical formula. What is incorrect about following statement?
determine the velocity of a cart traveling at 135cm in 5.5s.
Answer: 0.245 m/s
Explanation:
So velocity = d/t or distance over time in this case m/s or meters per second. But BE CAREFUL you must remember to convert cm to m always so 135 cm= 1.35m and 1.35m/5.5s= 0.245m/s
2.
You take a gas at 3 atm and increase the temperature from 120 K to 240 K. What is the final pressure?
A
6 atm
B
Not enough information
C
3 atm
D
1.5 atm
Answer:
A. 6atm
Explanation:
Using pressure law equation:
P1/T1 = P2/T2
Where;
P1 = initial pressure (atm)
T1 = initial temperature (K)
P2 = final pressure (atm)
T2 = final temperature (K)
According to this question;
P1 = 3 atm
P2 = ?
T1 = 120K
T2 = 240K
Using P1/T1 = P2/T2
3/120 = P2/240
Cross multiply
240 × 3 = P2 × 120
720 = 120P2
P2 = 720/120
P2 = 6atm
According to the graphs, by what factor will the ocean's acidity change from 2005 to 2100?
A) 0.2
B) 0.5
C) 1.6
D) 2.2
Answer: C) 1.6
Explanation: I got it right
calcium + zinc nitrate ------->
a) zinc + calcium chloride
b) there will be no reaction
c) zinc + calcium nitrate
d) calcium + zinc nitrate
Answer:
c
Explanation:
there will be displacement reaction taking place
Answer:
there will be no reaction
Explanation:
there will be no reaction since calcium does not displace zinc
Students report that the sky in their area has mostly cirrus clouds. What are most likely the weather conditions in the area?
rainy weather
dark, overcast (blocking the sunlight)
stormy weather
fair, pleasant weather
i’m not even sure if this is the right subject or like if this is even a question lol anyways
List at least 3 physical or chemical properties of the element Cobalt
Which of the following describes wind direction?
Wind direction is reported by the direction from which it originates. For example, a north or northerly wind blows from the north to the south. Wind direction is usually reported in cardinal (or compass) direction, or in degrees.
What element is in group 4 and period 3
A force of 25 newtons is exerted over an area of 50 square meters. Calculate
the pressure exerted in pascals.
Answer:
the pressure exerted in pascals is 0.5 Pa
Explanation:
The computation of the pressure exerted in pascals is shown below:
As we know that
Pressure = force ÷ area
= 25 ÷ 50
= 0.5 Pa
Hence, the pressure exerted in pascals is 0.5 Pa
We simply applied the above formula so that the correct pressure could come
list the factor on which Ka of a weak acid depends
A woman uses 330 Joules of energy to push a box across the floor in 33 seconds. What is her power output in Watts?
Answer:
10 watts
Explanation:
Power = Work / Time
Power = 330 J / 33 s
Power = 10 watts
Where is the potential energy to run the plant?
A 3
B
4
С
1
D
2
Answer: C
Explanation:
your well wisher
What are resistors? please help
Answer:Resistor Basics
Resistors are electronic components which have a specific, never-changing electrical resistance. The resistor's resistance limits the flow of electrons through a circuit.
They are passive components, meaning they only consume power (and can't generate it). Resistors are usually added to circuits where they complement active components like op-amps, microcontrollers, and other integrated circuits. Commonly resistors are used to limit current, divide voltages, and pull-up I/O lines.
Resistor units
The electrical resistance of a resistor is measured in ohms. The symbol for an ohm is the greek capital-omega: Ω. The (somewhat roundabout) definition of 1Ω is the resistance between two points where 1 volt (1V) of applied potential energy will push 1 ampere (1A) of current.
As SI units go, larger or smaller values of ohms can be matched with a prefix like kilo-, mega-, or giga-, to make large values easier to read. It's very common to see resistors in the kilohm (kΩ) and megaohm (MΩ) range (much less common to see miliohm (mΩ) resistors). For example, a 4,700Ω resistor is equivalent to a 4.7kΩ resistor, and a 5,600,000Ω resistor can be written as 5,600kΩ or (more commonly as) 5.6MΩ.
Schematic symbol
All resistors have two terminals, one connection on each end of the resistor. When modeled on a schematic, a resistor will show up as one of these two symbols:
Resistor schematic symbols
Two common resistor schematic symbols. R1 is an American-style 1kΩ resistor, and R2 is an international-style 47kΩ resistor.
The terminals of the resistor are each of the lines extending from the squiggle (or rectangle). Those are what connect to the rest of the circuit.
The resistor circuit symbols are usually enhanced with both a resistance value and a name. The value, displayed in ohms, is obviously critical for both evaluating and actually constructing the circuit. The name of the resistor is usually an R preceding a number. Each resistor in a circuit should have a unique name/number. For example, here's a few resistors in action on a 555 timer circuit:
Answer: resistor is
Explanation:
A resistor controls the flow of the electrical current within a circuit. Resistors are made from materials like copper or carbon, which make it difficult for the electrical charges to flow through a circuit. The most common type of resistor is a carbon resistor, which is a general purpose resistor, best suited for lower-powered circuits.
How many molecules of CrCl₃ are produced when 2.89 moles of CuCl₂ react? *
2Cr+3CuCI2-2CrCI3+3Cu
Explanation:
The reaction is CaCO
3
+2HCl→CaCl
2
+H
2
O+CO
2
.
Thus, 2 moles of HCl reacts with one mole of calcium carbonate to produce one mole each of calcium chloride, water and carbon dioxide respectively.
Hence, 3 moles of HCl will react with excess of calcium carbonate to produce 3×
2
1
=1.5 mol of carbon dioxide