Answer:
See explanation
Explanation:
If heat is given out in a reaction, then that reaction is exothermic. If heat is absorbed in a reaction, then that reaction is endothermic.
Hence, if heat is given out, the reaction is exothermic. The heat given out does work on the surrounding thus the laws of conservation of energy are obeyed.
Answer:
The reaction is exothermic.
Explanation:
I took the test
PLEASE HELP ASAP!!!
A teacher wrote the following part of a chemical equation involving water (H2O) and carbon dioxide (CO2): H2O + CO2 ---> ?
What is the most likely result of the chemical reaction represented by this equation?
A. H2CO3
B. NaCl
C. HNO3
D. H2Ca3
Answer:
Id say A. I think I hope I'm right
If you've got 3.011 X 10 ^ 24 atoms of Boron (B), how many grams do you have?
a
5.0 grams
b
54.055 grams
c
16.7 grams
d
1.82 grams
Using the table for electrode potential differences (Figure 2) identify the possible composition of the screws responsible for the corrosion observed in the contact area with the copper wire.
1.
Many plants can reproduce asexually. How is this an advantage for the plant? Why can it sometimes be a disadvantage
for the plant? Use details to support your answer.
Answer:
Advantage and disadvantage of asexual reproduction in plant is described below in details.
Explanation:
An advantage of asexual reproduction is that the resulting plant will approach adulthood quicker. Since the new plant is emerging from a grown-up plant or plant components, it will also be stronger than a seed. Asexual reproduction can take a spot by natural or manufactured (assisted by humans) means.
The significant disadvantages of asexual reproduction are the Shortage of diversity. Following the seeds are genetically the same as the parent they are more sensitive to the same diseases and nutrient insufficiencies as the parent. All the negative deviations endure for generations.
A scientist has 207.45g of H2O in a beaker. How many water molecules are in the beaker?
Answer:
6.94 x 10²⁴molecules
Explanation:
Given parameters:
Mass of water = 207.45g
Unknown:
Number of molecules = ?
Solution:
To solve this problem, we must understand:
1 mole of a substance contains 6.02 x 10²³ molecules
Now, first find the number of moles of water;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of water = 2(1) + 16 = 18g/mol
Number of moles = [tex]\frac{207.45}{18}[/tex] = 11.53moles
So;
1 mole of a substance contains 6.02 x 10²³ molecules
11.53moles of carbon dioxide will contain 11.53 x 6.02 x 10²³
= 6.94 x 10²⁴molecules
Hi guys . I'm having some troubles with physics and chemistry .
Do you know any sites or apps that can help me with any topic in physics and chemistry ( apart from Khan academy ) ?
Note : The site or app has to be able to teach and explain topics in Physics and Chemistry .
Explanation:
byju's ig. Cause it gives a proper concept
Why are noble gases, like helium and krypton, unlikely to form a bond?
A. They do not have valence electrons and therefore cannot form bonds by sharing or trading
electrons.
B. They always have an equal number of protons and electrons.
C. They have full valence
orbitals and already have low energy.
D. They are nonmetals and gases and therefore their ionization energy is too high to form a bond.
Answer:
The valence electrons are the only parts of an atom that make chemical bonds. Noble gases don't form chemical bonds because they have a full outer shell (8 electrons).
I’m learning about heredity
1. How can environment influencers inherited traits
2. How many chromosomes do humans have? Explain where these chromosomes come from.
Answer:
1. (See explanation)
2. 46. 23 from the mother’s egg and 23 from the father’s sperm.
Explanation:
ok for number one I am not entirely sure, but I am pretty sure that light, chemicals and temperature can all affect which genes get turned on and off. I am not entirely sure if the question is asking about the environment influencing inherited traits in the form of natural selection tho? If that is something you’re seeing right now, it might be a possible answer. But honestly I am not completely sure.
Moraines left by glaciers are different from deposits left by rivers because the rocks left behind are _____.
Explanation:
unorganized and unsorted i think this is the answer
The picture provided shows the arrangement of electrons in atomic shells around the nucleus of four different elements.
Which statement is true about these elements?
A) All elements belong to the same period.
B) All elements belong to the same group.
C) Elements 1 and 4 belong to the same group.
D) Elements 2 and 3 belong to the same period.
Both element 1 and element 4 have one electron in their valence shell Therefore, they belong to the same group. Therefore, option (C) is correct.
Why do elements of the same group have similar chemical behavior?The chemical behavior of elements will depend on the number of electrons in their outermost shell. Elements that are placed in the same group have the same number of valence electrons. Therefore, elements present in the same group of the modern periodic table have similar chemical properties.
The elements with a similar outer shell electronic configuration in their atoms are organized in the same group of the modern periodic table. These valence electrons of an element are responsible their chemical properties and reactivities of the elements.
Elements 1 and 4 have one electron in their valence shell so they belong to the same group while elements 2 and 4 have two electrons in their valence shell that also belong to the same group.
Learn more about elements with similar chemical behavior, here:
brainly.com/question/5364617
#SPJ2
USE LETTERS FOR ANSWERS, NO NEED TO EXPLAIN
a) Substitute symbols and formulas for words.
b) Predict the products. If no reaction occurs, write “NR” after the --> sign. c) Include abbreviations for the physical state.
d) Write out and balance the equation.
6. Mercury is poured into an aqueous solution of zinc nitrate.
7. Solutions of potassium iodide and lead (II) nitrate are mixed. The resulting lead compound is a precipitate.
thank you! :)
Answer:
Ok:
Explanation:
6a) [tex]Hg + Zn(NO_3)_2\\[/tex]
b) NR
c) [tex]Hg_{(l)} + Zn(NO_3)_2 {(aq)}=> NR[/tex]
d) Welp, no reaction so i don't know.
7a) [tex]KI + Pb(NO_3)_2[/tex]
b) [tex]PbI_2 + KNO_3[/tex]
c) All are aqeuous except for PbI2 which is solid
d) [tex]2KI _{(aq)}+ Pb(NO_3)_2_{(aq)} => PbI_2_{(s)} + 2KNO_3_{(aq)}[/tex]
Check if that is ok or if my work has any issues :).
(60 points + brain list) The correct electron configuration of the O2-ion is
A)
2-4
B)
2-5
C)
2-7
D)
2-8
I have no idea what the answer is
ill guess c
Explanation:
g
How many grams are in 2.0 moles of iron(III) carbonate?
Explanation:
1 mole is equal to 1 moles Iron(III) or 832.29538 grams, so 2 moles Iron(III) = 1664.59076 grams
PLZ HELP!
How does changing the angle of a ramp affect the force required?
Answer:
depending on how you change the angle on the ramp the kanetic energy can go up or down depending on how u angle the ramp
Explanation:
Describe how the composition of the upper mantle is different from the lower mantle?
a. The upper mantle is made of solid rocks and lower mantle is made of melted rocks and minerals
b. The upper mantle is made of melted rocks and minerals and lower mantle is made of solid rocks
c.The upper mantle is made of lava and the lower mantle is made of magma
Answer:
b
Explanation:
Answer:
it is B hope I helped
=
Explanation:
PLEASE HELPPP!!!!!! ASAP!!!!
Which of the following best describes cations? Question 19 options: A) They're negatively charged because they lost an electron. B) They're positively charged because they gained an electron. C) They're positively charged because the number of electrons remained the same. D) They're positively charged because they lost an electron.
Answer:D
Explanation:trust me bro
Answer:
D
Explanation: I took the test
The compound has the empirical formula of CH. Give some possible molecular formulas for this compound if you didn't know the molar mass.
Answer:
Convert the mass of each element to moles using the molar mass from the periodic table. Divide each mole value by the smallest number of moles calculated. Round to the nearest whole number. This is the mole ratio of the elements and is represented by subscripts in the empirical formula.
Explanation:
The result is the molecular formula
3. The air today is approximately one-fifth
oxygen. Calculate the approximate volume of
oxygen in 200cm3 of air.
Answer: 40cm^3
Explanation:
Since the The air today is approximately one-fifth oxygen, the approximate volume of oxygen in 200cm3 of air would be:
= 1/5 × 200
= 40cm
The answer is 40cm^3
We add 5.0 g of sugar to 100 mL of water.
What is the mass of the solution?
The mass of the solution : 105 g
Further explanationGiven
5 g sugar
100 ml water
Required
The mass of the solution
Solution
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:
[tex]\large {\boxed {\bold {\rho ~ = ~ \frac {m} {V}}}}[/tex]
ρ = density
m = mass
v = volume
Density of water = 1 g/ml
So mass of water :
= density x volume
= 1 g/ml x 100 ml
= 100 g
So total mass of solution :
=mass sugar+mass water
= 5 g + 100 g
= 105 g
Where did you walk? what did you find most enjoyable while walking: listening to music, listening to an audio book, or nothing? how did your body react to this introductory amount of exercise? was it more exercise or less exercise than you are used to? if you did not walk, what other type of physical movement did you do?
Answer: walked from school few blocks before arriving .found charting and laughing with my pals most enjoyable while I was walking .my body reacted by tiredness, it is less exercise than I am capable of doing.
Explanation: did that help?
The best description of the Big Bang Theory is ______________
A. The universe began with cold dense energy compressing into matter after which all matter and energy began rapidly contracting toward each other.
B. The universe began with hot dense energy compressing into matter after which all matter and energy began rapidly expanding away from each other.
C. The universe began with hot dense matter after which all energy began rapidly expanding away from each other.
D. The universe began with cold, spread out matter compressing into energy, after which all matter and energy began slowly moving toward each other
Answer:
B. the universe began with hot dense energy compressing into matter after which all matter and energy began to rapidly expanding away from each other.
hope it helps
pls asap figure it out pls I will mark brainliest
Answer:
NaCl (Na is a metal and Cl is a nonmetal) MgO (Mg is a metal and O is a nonmetal) Al2O3, NaF, Na2O
Explanation:
You have to have a metal and a non metal together for it to be ionic
An object has a density of 40 g/cm3 and a mass of 240 g what is it’s volume
Answer:
6cm^3
Explanation:
240/40=6
6 cm^3
You push 100kg door with force of 200 with what force does the door push back on you
Answer:
for every action there is equal and oposite reaction so door als pushes us back with same force. ie;200N.
I need help with my worksheet
Balance the equation
__Nal +__ F = ___NaF + __l
2 2
Answer:
2NaI + F₂ → 2NaF + I₂
Explanation:
Chemical equation:
NaI + F₂ → NaF + I₂
Balanced chemical equation:
2NaI + F₂ → 2NaF + I₂
The given reaction is single replacement reaction.
Step 1:
NaI + F₂ → NaF + I₂
left hand side Right hand side
Na = 1 Na = 1
I = I I = 2
F = 2 F = 1
Step 2:
2NaI + F₂ → NaF + I₂
left hand side Right hand side
Na = 2 Na = 1
I = 2 I = 2
F = 2 F = 1
Step 3:
2NaI + F₂ → 2NaF + I₂
left hand side Right hand side
Na = 2 Na = 2
I = 2 I = 2
F = 2 F = 2
If the gas tap to the Bunsen burner is turned on, the methane does not start burning until it is lit with a match. Why is heat from the match needed to start the methane burning?
Answer:
The reaction has a high activation energy
Explanation:
The burning of methane is a spontaneous reaction. Once the burning begins, the flame is able to sustain itself without any additional input of energy. It is an exothermic reaction in which energy is given out in the form of heat.
The reason why heat from the match is needed to start the burning of methane is that the activation energy of the combustion of methane is high. Activation energy is the energy that must be supplied in order for the collision of reactants to result in chemical reaction.
As long as the activation energy is high, the reaction can not occur without an external input of energy (e.g striking a match). Hence the answer.
The electron configuration of an element is 1522s22p63523p6451. Why is this a REPRESENTATIVE element?
A)
All orbitals are completely filled.
B)
The outermost electron is a valence electron.
The outermost electron is added to the p-orbital.
D
The highest s-orbital or p-orbital is partially filled.
8. __H2 + __O2-> __H2O
9. __K2SO4 + __H2-> __H2SO4 + __K
10. __NO2 + __H2O-> __HNO3 + __NO
Which electron configuration could represent the electrons in a Sodium atom in an excited state?
Answer:
I think Ne electron configuration
Answer:
D 2-7-2
Explanation:
I got it wrong and then they showed me the right answer
