Answer:
1.51×10²³ atoms.
Explanation:
From the question given above, the following data were obtained:
Mass of Calcium (Ca = 10 g
Number of atom of Calcium (Ca) =?
The number of atoms present in 10 g of Ca be obtained as follow:
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02×10²³ atoms. This implies that 1 mole Ca contains 6.02×10²³ atoms.
1 mole of Ca = 40 g.
Now, if 40 g of Ca contains 6.02×10²³ atoms.
Therefore, 10 g of Ca will contain = (10 × 6.02×10²³) / 40 = 1.51×10²³ atoms.
Thus, 10 g of calcium contains 1.51×10²³ atoms.
Someone please help i don’t have much time left
Answer: Energy of reactants = 30, Energy of products = 10
Exothermic
Activation energy for forward reaction is 10.
Explanation:
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and [tex]\Delta H[/tex] for the reaction comes out to be negative.
Energy of reactants = 30
Energy of products = 10
Thus as energy of the product < energy of the reactant, the reaction is exothermic.
Activation energy [tex](E_a)[/tex] is the extra energy that must be supplied to reactants in order to cross the energy barrier and thus convert to products.
[tex]E_a[/tex] for forward reaction is (40-30) = 10.
A molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor A molecule or ion that binds to this hydrogen is a hydrogen bond acceptor. Specify the hydrogen bonding behavior of the 4 species below by selecting: donor for species that act as donors only acceptor for species that act as acceptors only both for species that act as both donors and acceptors neither for species that act neither as donors nor as acceptors.
The question is incomplete, the complete question is found in the image attached.
Answer:
1- acceptor
2-donor
3-acceptor
4-donor
Explanation:
A hydrogen bond acceptor is a molecule that has an electronegative atom having a lone pair of electrons that participates in the hydrogen bond.
A hydrogen bond donor is the molecule that supplies the hydrogen atom of a hydrogen bond.
If we look at structure I-IV in the image attached, I and III are hydrogen bond acceptors because they all possess electronegative atoms having lone pairs of electrons but do not have hydrgen atoms bonded to highly electronegative atoms.
Similarly, structures II and IV are hydrogen bond donors. The C=C double bond is electron withdrawing and highly electronegative making the hydrogen atoms attached to it acidic and hydrogen bond donors. Also, nitrogen is an electronegative atom thereby making structure IV a hydrogen bond donor.
Which factors directly affect the magnetic force produced by an electromagnet?
O number of turns in the wire, amount of current
O amount of current, type of force
O length of core, number of turns in the wire
O amount of current, length of core
Does sugar make children hyperactive?
Answer:
yes it does
Explanation:
Answer:
Yes
Explanation:
Trust me I know :/
an organic pesticide was decomposed by an oxygen combustion procedure to convert the chlorine in the molecule to water soluble chloride the chloride was then precipitated as AgCl A 0.7715 gram precipitate was obtained from 500 grams of pesticide Calculate the percentage chlorine in the pesticide
Answer:
0.0382%
Explanation:
Given that:
Silver chloride = AgCl
Molar mass of AgCl = (107.87 + 35.5) = 143.37 g/mol
Chlorine, Cl = 35.5
143.37g/mol of AgCl = 35.5 g of Cl
Hence, 1 g AgCl will give ; (35.5 / 143.37)
1g AgCl = 0.2476 g Cl
In 0.7715 g AgCl, ; (0.2476*0.7715) g Cl
= 0.1910 g Cl
Therefore, percentage of Cl in 500g sample:
(Mass of Chlorine / mass of sample) * 100%
(0.1910 / 500) * 100%
0.000382 * 100%
= 0.0382%
How many grams of SO3 can be produced if 3.3 moles of O2 reacts?
An ideal gas is in a sealed rigid container. The average kinetic energy of the gas molecules depends most on An ideal gas is in a sealed rigid container. The average kinetic energy of the gas molecules depends most on the temperature of the gas. the number of molecules in the container. the size of the container. the mass of the molecules.
Answer:
The temperature of the gas.
Explanation:
According to the kinetic molecular theory, the molecules of a substance are in constant random motion.
If an ideal gas is contained is a sealed rigid container, the average velocity of the gas molecules is dependent of the temperature of the gas.
Recall that temperature is defined as the average kinetic energy of the molecules of a body.
HELLOSOEOODORODODODORRLKRKLRLRLF
Answer:
I'd say maybe Dangerous? I hope this helps
Answer:
golden is sometimes referred to as shiny and beatitful
Explanation:
Calculate the enthalpy change with the help of Hess’s law for the decomposition of hydrogen peroxide, (2H O (l) ------- 2H O(l) + O (g)), if the enthalpy of formation of water (2H (g) +O (g)) is –512KJ and vaporization of hydrogen peroxide (H O (l) = H (g) + O (g)) is 376 kJ.
Answer:
Explanation:
For answer see attached file .
Do atoms have the same number of protons as its neutrons? I know that atoms can have different number of electrons compared to protons, but does the number protons and neutrons stay equal?
An scientist located a nugget of an unknown substance. However, he determined that this nugget has a
mass of 63 g and a volume of 9 cm^3. What is the density of this nugget?
Answer: The density of this nugget is [tex]7\text{ g cm}^{-3}[/tex] .
Explanation:
We are given that,
Mass of nugget = 63 g
Volume = [tex]9\ cm^3[/tex]
The computation of density of a substance is given by :-
[tex]\text{Density}=\dfrac{\text{Mass}}{\text{Volume}}\\\\\Rightarrow\ \text{Density}=\dfrac{63}{9}\text{ g cm}^{-3}[/tex]
[tex]\Rightarrow\ \text{Density =}7\text{ g cm}^{-3}[/tex]
Therefore, the density of this nugget is [tex]7\text{ g cm}^{-3}[/tex] .
Cleavage refers to the way a rock:
A. shine
B. breaks
C. streaks
D. is made
Explanation:
Türküm ben yanlisikla siteye girdim.
Answer:
breaks
Explanation:
I think its braks
How does changing the number of electrons in an atom affect the atom?
Which energy transformation occurs when you rub your hands together to warm them?
kinetic energy to radiant energy
thermal energy to kinetic energy
thermal energy to potential energy
want energy to thermal energy
Explanation:
The answer is thermal energy/ kinetic energy.. because friction on hands promotes thermal energy. because you want your hands 2 be warm, rubbing them 2gether creates heat and absorption of heat thru the skin which skin is susceptible to warm, humans can put hands under arm pits to warm hands, without any available heat source..
The reactants of two chemical equations are listed.
Equation 1: AgNO3 + Zn
Equation 2: AgNO3 + MgCl2
Based on the type of reaction, which reaction can be used to extract silver metal from silver nitrate solution?
Answer: Equation 1, because Zn being more reactive, replaces Ag from AgNO3
Explanation: I got it right on the quiz and it replaces it
Which statement gives a disadvantage of multicellular organisms?
A. They need small amounts of energy
B. They reproduce slower than unicellular organisms
C. They can perform more functions
D. Cells are able to provide support
Answer: B. They reproduce slower than unicellular organisms
Explanation:
In unicellular organisms there is a single cell which performs all the functions like digestion, respiration, and reproduction. The cell reproduce by cell division. The single parent cell divides into two identical daughter cells. But multicellular organisms exhibit multiple cells and their reproduction is complex. They reproduce by sexual mode of reproduction in which separate sex cells are produced when they fuse form zygote which is the precursor of new organism. This process is slower than that of the cell division and production of progeny by the unicellular organisms. Thus reproduction is slower in multicellular organism this is the disadvantage in multicellular organisms.
Answer:
B. they reproduce slower than unicellular organisms
Explanation:
The columns in the periodic table are called groups. What do the elements in group 17 have in common?
Answer:
All of the elements in group 17 all have 7 valence electrons. This is one thing they all share in common.
Explanation:
Which of these has the most kinetic energy?
A. a 25 kg fish tank sitting on a table
B. a .05 g fish swimming in a fish tank
C. a 7,500 kg car parked on a steep hill
D. a 50 kg boulder suspended from a cliff
The empirical formula of a hydrocarbon (compound that contains only C and H is found to be CH. laboratory procedures have found that the molar mass of the compound is 78 g/mol. What is the molecular formula of this compound
Answer:
C₆H₆
Explanation:
Molar mass of the compound is 78g/mol
Unknown:
Molecular formula of the compound = ?
Solution:
The empirical formula of the compound is CH.
Empirical formula is the simplest formula of a compound.
To solve this problem:
Find the molar mass of CH;
Molar mass = 12 + 1 = 13g/mol
Multiplication index = [tex]\frac{78}{13}[/tex] = 6
So;
(CH)₆ ;
Therefore:
C₆H₆
A force of 100 newtons was necessary to lift a tree. A total of 50 joules of work was done. How far was the tree lifted
Answer:
Distance lift the tree = 0.5 m
Explanation:
Given:
Work done = 50 joules
Force = 100 newton
Find:
Distance lift the tree
Computation:
Distance = Work done / Force
Distance = 50 / 100
Distance = 0.5 m
Distance lift the tree = 0.5 m
Which element in group 17 has the highest ionization energy
Answer:
fluorine
Explanation:
it has the highest electronegativity in the group and in the periodic table
a A student decreases the temperature of a 484 cm ^ 3 balloon from 570 K to 285 Assuming constant pressure, what should the new volume of the balloon be? Round your answer to one decimal place.
Answer:
242 cm³.
Explanation:
The following data were obtained from the question:
Initial volume (V₁) = 484 cm³
Initial temperature (T₁) = 570 K
Final temperature (T₂) = 285 K
Pressure = constant
Final volume (V₂) =?
The new volume (i.e final volume) of the balloon can be obtained by using the Charles' law equation as illustrated below:
V₁/T₁ = V₂/T₂
484 / 570 = V₂ / 285
Cross
484 × 285 = 570 × V₂
137940 = 570 × V₂
Divide both side by 570
V₂ = 137940 / 570
V₂ = 242 cm³
Therefore, the new volume of the balloon is 242 cm³
Which water usage uses the least amount of water in a year in the United States? a industry
b livestock c irrigation d public water supply
plzzzzzzzz hurrrrry
how many atoms of Na are there in 0.17 moles of Na
Answer:
1.023 × 10²³ atomsExplanation:
The number of atoms in a substance can be found by using the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
N = 0.17 × 6.02 × 10²³
We have the final answer as
1.023 × 10²³ atomsHope this helps you
The density of a sample of gasoline is 0.70 g/cm3. What is the mass of 1 liter of this gasoline?
Group of answer choices
0.7 g
70 g
700 g
1,429 g
Answer:
700g
Explanation:
Given parameters:
Density of gasoline = 0.7g/cm³
Volume of gasoline = 1L = 1000cm³
Unknown:
Mass of the gasoline = ?
Solution:
Density is the mass per unit volume of a substance. It can be expressed as;
Density = [tex]\frac{mass}{volume}[/tex]
So;
Mass = density x volume
Mass = 0.7 x 1000 = 700g
Atoms of arsenic (As) are often added to silicon (Si) in a process called doping to change the conductivity of the silicon. How does the addition of arsenic change the conductivity of silicon?
a) An atom of arsenic has one fewer valence electron and more electron shells than an atom of silicon, so the conductivity decreases because the arsenic atom gains an electron.
b) An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity decreases because the arsenic atom loses the electron.
c) An atom of arsenic has one fewer valence electron and fewer electron shells than an atom of silicon, so the conductivity increases because the arsenic atom gains an electron.
d) An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity increases because the arsenic atom loses the electron.
HAD TO POST THIS THIS BC THE OTHER POSTED IS WRONG
Answer:
d) An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity increases because the arsenic atom loses the electron.
Explanation:
This is an example of a n-type semiconductor. The additional electron introduced to the 'grid' of silicon atoms causes an increase in the conductivity of the silicon. This additional electron is introduced as arsenic loses its extra electron.
Answer:
D is the answer, the other one is wrong.
Explanation:
4.Calculate the Hydroxide, Hydrogen ion and POH of solution if the PH of solution is 7.b
5.Solution A Has PH =4 and solution B has PH = 7.How many times greater is the Hydroxide ion
concentration in solution A than the Hydronium ion concentration in solution B
the ph is gonna be your value and the 4 is gonna be your main subject
so as the ph is your value u gonna ad your ph and 7 and 4 toghter then multiple your answer 2 times because ph represent multiple and your value
1. All the following are correctly balanced except -
A. 2C2H2 + 502 4CO2 + 2H20
B. 4Fe + 302 – 2Fe2O3
C. NaHCO3 Na2CO3 + H2O + CO2
D. 2CH,OH + 302 2C02 + 4H20
A species of desert plant produces flowers that only bloom at night. How does this enhance the survival of the species?
A. This allows the plants to conserve water and not bloom during the heat of the day.
B. This species relies on nocturnal animals like moths for pollination and reproduction
C. This species relies on moonlight for photosynthesis.
D.This allows flowers to stay closed durng the day when herbivores are more likely to eat them.
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Answer:
A. This allows the plants to conserve water and not bloom during the heat of the day
Explanation:
Most desert plants only bloom at night because they take advantage of animals like moths and insects that fly at night for pollination and reproduction.
Because these plants are in the desert and do not get enough water except from short occasional rainfalls, they conserve water and not bloom during the heat of the day. They bloom at night when the temperature is low and this enhances their water conservation and survival.
when you tapped the stick on one end of the tape, did you see a wave that
formed and rolled down the line? Write your observations.
Answer:
Yes.
Explanation:
Yes, I did see a wave that formed and rolled down the line because of tapping the stick on one end of the tape. The wave that had been created goes from one side of the tape to the other end of the tape. This movement occur in the tape due to the disturbance at one end of the tape so we can say that wave formed in the tape and rolled down the line.