Answer:
70
Explanation:
The atomic number stands for the number of protons.
mass number stands for number of neutrons and protons.
30 neutrons + 40 protons = mass number of 70
Hope this helps!
Today, the atom is defined as the_____ particle that can still be considered an____.
Answer:
Today, the atom is defined as the smallest particle that can be considered an element.
Explanation:
Answer:
Today,the atom is defined as the smallest particle that can still be considered an element.
which of the beryllium halides are considered ionic compounds?
Answer:
Beryllium Fluoride (BeF2) is an ionic compound
A student must use 225 mL of hot water(cwater=4.184 J/g°C) in a lab procedure. Calculate theamount of heat required to raise the temperature of225 mL of water from 20.0 °C to 100.0 °C.
Answer: q = 64 kJ
Explanation:
As you know, a substance's specific heat tells you how much heat is required to increase the temperature of
1 g
of that sample by
1
∘
C
.
In water's case, you know that its specific heat is equal to
4.18
J
g
∘
C
. This tells you that in order to increase the temperature of
1 g
of water by
1
∘
C
, you need to supply
4.18 J
of heat.
How much heat would you need to increase the temperature of
200 g
of water by
1
∘
C
?
Well, if you need
4.18 J
per gram to increase its temperature by
1
∘
C
, it follows that you will need
200
times more heat to get this done.
Likewise, if you were to increase the temperature of
1 g
of water by
76
∘
C
, you'd need
76
times more heat than when increasing the temperature of
1 g
by
1
∘
C
.
Combine these two requirements and you get the total amount of heat required to increase the temperature of
200 g
of water by
76
∘
C
.
Mathematically, this is expressed using the following equation
q
=
m
⋅
c
⋅
Δ
T
, where
q
- heat absorbed/lost
m
- the mass of the sample
c
- the specific heat of the substance
Δ
T
- the change in temperature, defined as final temperature minus initial temperature
Plug in your values to get
q
=
200
g
⋅
4.18
J
g
∘
C
⋅
(
100
−
24
)
∘
C
q
=
63536 J
I'll leave the answer rounded to two sig figs and expressed in kilojoules
q
=
64 kJ
4. Balance the following equations (show work)
a.___H2(g) +___O2(g) →___H2O(1)
b.____Fe(s) +___O2(g)→___Fe2O3(s)
c.___Al(s) +___HCl(aq) →___AlCl3(aq) +___H2(g)
d.____CaCO3(s) +____HCl(aq) →____CaCl2(aq) +____CO2(g) +____H2O(1)
Answer:
a) 2H2+O2 = 2H²O
b) 4Fe+30²=2Fe²O³
c) 2Al+6HCl=2AlCl³+3H²
Please help me..
Will give the brainliest
Urgent
Please answer correctly
Explanation:
a) blue litmus paper turns red when u add acid in it .
b) red litmus paper , when an alkali dissolves in water it produce hydroxide ions
which cause it to become a alkaline
Use your knowledge of valence electrons and how they affect bonds to figure out how carbon (Group 14) and oxygen (Group 16)
would be attached to one another. In carbon dioxide (CO2), how is the compound structured? (Use "-" to represent a single
bond and "=" to represent a double bond) (1 point)
C-O-O
O=C-O
C=O-O
O=C=O
Answer: D
Explanation:
O=C=O
Carbon is in group 14 having four valence electrons and oxygen is in group 16 having six valence electrons hence the correct structure of CO2 is O=C=O.
Carbon and oxygen are nonmetals. Nonmetals form compounds by sharing electrons in a covalent bond.Carbon, a group 14 element has four valence electrons while oxygen, a group 16 element has six valence electrons.
Carbon can share four valence electrons with two oxygen atoms in CO2 to form the structure O=C=O. In this way, all the atoms now obey the octet rule.
Learn more: https://brainly.com/question/865531
why should you not change the subscripts in chemical formulas when balancing chemical equations?
Answer:because the chemical formula is vital to the equation it tells you what creates the chemical and whats in it you can change the exponents but not the formula itself
Explanation:
Which of the following is an intensive physical property?
(A) color
B) volume
C)
length
D)
mass
Color is an example of an intensive physical property. Details about intensive physical property can be found below.
What is intensive property?Intensive properties are physical properties that does not depend on the mass of the substance or system.
Another property of substances is the extensive property, which is the property that is dependent on the quantity of the substance.
Examples of intensive physical properties are as follows:
ColorDensityTemperaturePressureLearn more about intensive property at: https://brainly.com/question/13733851
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Fill in the blank
Atomic Number (____) = the number of ________________ or the number of ___________________.
Atomic Mass Number (____) = the number of ________________ PLUS the number of ______________.
Answer:
Atomic number (smaller number) =number of protons or number of electrons
mass number ( larger number) =number of protons plus the number of neutrons
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Answer:
sana all may brainnnnnnnnnnnnn
Someone pls help me I will make you brain
Answer:
D, radiation
Explanation:
the sun's heat radiates onto the land, oceans, and surrounding atmosphere, warming them
What two factors must be held constant for density to be a constant ratio?
The two factors which must be held constant for density to be a constant ratio are: Mass and Volume
As we know, the density of a material is simply defined as the ratio of mass to volume.
In essence, Density = Mass/VolumeConsequently, To obtain a constant ratio for density, the mass and volume of the material in discuss must be kept constant.
Read more;
https://brainly.com/question/17780219
Copperhead snakes can reproduce both sexually and asexually. which option describes a situation where sexual reproduction is more advantageous for the copperhead snake.
A. a new disease develops , so having more genetic variation among there off spring is an advantage.
B. a new type of pray arrives in the environment , so they have more food sources.
C. a short and mild winter makes the environment more livable for them and all the other organisms in the area.
D. they migrate to a new location where prey and shelter are more abundant and easier to find.
Answer:
Answer A:
a new disease develops , so having more genetic variation among there off spring is an advantage.
Not 100% sure but A seems the most likely answer.
Explanation:
The question is asking where sexual reproduction is more of an advantage and I'd say that having more genetic variation would be caused by sexual reproduction and not as much or at all in asexual reproduction.
with B, C, and D. It wouldn't really be an advantage to do one or the other in this context.
hỗn hợp E gồm 6 este có cùng CTPT C8H8O2 và đều chứa vòng benzen. Cho 68g phản ứng tối đa với V ml dd NaOH 1M đun nống, thu được 15g muối và 77,4g hh ancol Y. Giá trị của V là?
Explanation:
just a few days ago and I have a
30 g of hydrogen reacts with 120 g of oxygen to form water.How much water is produced?
136.9 g of copper sulfide breaks apart into sulfur and 111.6 g of copper.How much sulfur is produced?
According to law of conservation of mass.
In a chemical reaction Mass is neither created nor destroyed.
Mass of product =Mass of reactant#1
Mass of water
[tex]\\ \sf\longmapsto 30+120=150g[/tex]
#2
Mass of sulphur:-
[tex]\\ \sf\longmapsto 136.9-111.6=25.3g[/tex]
Explain why titritations using permanganate are performed in Acid solutions
The titration using permanganate in acidic solution because it can be act as behave indicator.
What is titration?Titration is a typical quantitative chemical analysis procedure used in laboratories to quantify the concentration of a specified analyte. The titrant or titrator is a substance that is manufactured as a standard solution with a given concentration as well as volume.
Permanganate titrations must be performed in a strong acid solution. Because [tex]HNO_{3}[/tex] and HCl might involve in competing for a redox reaction, lowering the accuracy of the titration, sulfuric acid is commonly utilized. Titration permits food manufacturers to calculate the amount of a reactant present in a sample.
To know more about titration.
https://brainly.com/question/2728613.
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Letter C shows that some of the heat rising from the earth's surface is trapped by gases in the atmosphere and reflected back to earth. This is known as what?
options:
Coriolis Effect
Solar Flares
Green House Effect
Windshield Effect
This painting is showing the actions of American colonists at the 1773 protest known by what name? A) The Plymouth Rocks B) The Boston Massacre C) The Boston Tea Party D) The New York Draft Riots
that will be the Boston tea party
Explanation: C) the Boston tea party
I did the quiz
Which group on the Periodic Table has elements that would easily combine with elements from Group 1 (which have one valence electron) because they have 7 valence electrons?
Answer:The halogens in Group 17
Explanation: The halogens in Group 17 all have 7 valence electrons. They will steal anuy electrons they can to form a full outer shell.
solar powered cars use energy use energy form the sun to work. a panel on the car absorbs light energy from the sun, which then generates a electric current. this electric current, in turn allows this car to move. which shows the correct order of energy transformations that take place in a solar-powered car? A. electrical, chemical, kinetic B. electrical, kinetic, radiant C. radiant, chemical, electrical D. radiant, electrical, mechanical. i will brainliest to fastest answer
Answer:
The answer is
D)
radiant, electrical, mechanical
Explanation:
During photosynthesis,blank energy is transformed into blank energy
Answer:
I am also beginners I don't know I am only completing this answer and sorry!!!!!!
Answer:
Solar Energy and Chemical energy
Explanation:
An atom of oxygen (atomic number 8) has a mass number of 17. How many neutrons are
in that atom?
# of neutrons = mass number - atomic number
= 17 - 8
= 9
∴ number of neutrons in an atom of oxygen of mass number 17, is 9.how long ago did two organisms that show 20 differences in their genetic sequences diverge?
Answer:
Comparison of whole genome sequences provides a highly detailed view of how organisms are related to each other at the genetic level.
Explanation:
I NEED HELP ASAP PLEASE
Answer: I am sorry i couldnt answer but this question is beyond me
Explanation:
HELPP PLEASE!!!
What kind of metal is Co?
Alkali Metal
Transition Metal
Alkaline Earth Metal
Answer:
Transition Metal
Explanation:
Hey there is a really easy tool called PTable that is an interactive periodic table that does all kind of things. needed in Chem
What are the valence electrons of an atom?
A.The electrons that remain closest to the nucleus
B.The electrons that an atom gains when it becomes an anion
C.The electrons that an atom loses when it becomes a cation
D.The electrons in the highest occupied energy level
Answer:
D
Explanation:
Valence electrons are the electrons in the highest occupied principal energy level of an atom.
A wind turbine transfers energy from
energy stores. What one word
completes the sentence?
Answer:
The word "transfers" completes the sentence.
Explanation:
A wind turbine transforms the mechanical energy of wind into electrical energy. A turbine takes the kinetic energy of a moving fluid, air in this case, and converts it to a rotary motion. As wind moves past the blades of a wind turbine, it moves or rotates the blades. These blades turn a generator.
Hope This Helps!
Answer:
The right answer is "kinetic"
Explanation:
Wind is moving, so has kinetic energy.
Could someone help me
Answer:
The space in the container so how small it is the more pressure is going to build up. YOUR WELCOME AND HAVR A GOOD DAY.
Do you think acid rain makes new substances? (CER)
Not all chemical reactions are spectacular. They do not always involve substances that you think of as chemicals like the ones in the lab or in acid rain. ... When molecules of sulfenic acid get to your eyes, they can react with the water in your eyes to produce a new substance, a form of sulfuric acid.
how many atoms of oxygen o are represented on the left side of the arrow in the chemical reaction
Answer:
two oxygen atoms on the left side of the arrow