Nucleus is present at the centre of atom. It contains protons and neutrons. It is very small as compared to the atom.
Answer:
It is a part of a cell which controls all the activities in the cells and contains the genetic information of the cell that is to be passed down to the next cell when it reproduces.
Explanation:
It is a part of a cell which controls all the activities in the cells and contains the genetic information of the cell that is to be passed down to the next cell when it reproduces.
The free flow of electrons is responsible for
Answer:
An electrical phenomenon is caused by flow of free electrons from one atom to another. The characteristics of current electricity are opposite to those of static electricity. Wires are made up of conductors such as copper or aluminum.
Explanation:
from google
how many elements are found in the third period. A.2 B.18 C.8 D.32
Answer:
8
Explanation:
u can find it on ur chemistry book
Answer:
C. 8
Explanation:
Check chemistry textbook
is 4 Fe + 3 O2 --> 2 Fe2O3
balanced?
Answer:
Yes the given equation is balanced.
Explanation:
Chemical equation:
Fe + O₂ → Fe₂O₃
Balanced chemical equation:
4Fe + 3O₂ → 2Fe₂O₃
There are four iron and six oxygen atoms on both side of equation thus the given equation is balanced.
The given reaction also follow the law of conservation of mass.
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
This reaction is synthesis reaction:
Synthesis reaction:
It is the reaction in which two or more simple substance react to give one or more complex product.
A + B → AB
When is my dad going to get the milk?
Answer:
joe.......
Explanation:
mama......
How many moles of aluminum are equivalent to 4.816 × 1024 atoms?
A.12.5
B.8
C.1.25
D.08
Answer:
6.591
Explanation:
= 6.951 moles
Answer: 8
Explanation:
If the specific heat of water is 4.18 3/g*^ C much heat is required to increase the temperature of 12 g of water from 23 degrees * C to 39 degrees * C ^ 2
Answer:
Q = 802.6 J
Explanation:
Given data:
Specific heat capacity of water = 4.18 J/g.°C
Mass of water = 12 g
Initial temperature = 23°C
Final temperature = 39°C
Heat required = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 39°C - 23°C
ΔT = 16 °C
Q = 12 g× 4.18 J/g.°C × 16 °C
Q = 802.6 J
List three things, other than the name, symbol, atomic number, and average atomic mass, you can discover about an element using the periodic table in Figure 6.9.
Answer: State of matter, Subcategory in the metal-metalloid-nonmetal trend, and electrons per shell.
Explanation:
How are ionic compounds named?
Answer:
Ionic compounds are neutral compounds made up of positively charged ions called cations and negatively charged ions called anions. For binary ionic compounds (ionic compounds that contain only two types of elements), the compounds are named by writing the name of the cation first followed by the name of the anion.
Explanation:
Hope this helps.
d Which properties of plastics cause a problem when the container is empty?
Answer: Both of these are of great concern to human health. BPA is used in many things including plastic bottles and food packaging materials. Over time the polymer chains of BPA break down, and can enter the human body in many ways from drinking contaminated water to eating a fish that is exposed to the broken down toxins.
Explanation:
I think you will get it
HELPPPPPPPPP 35 POINTSSSSSS!!!!!FILL IN THE BLANKS with either "reduce" or "oxidize"
Magnesium is able to ——copper, and copper is able to —— magnesium.
Zinc is able to—— magnesium, and magnesium is able to—— zinc.
Copper is able to—— zinc, and zinc is able to—— copper.
Look at my screenshot:
FeO+ PdF2 ---> FeF2+PdO balance please worth 50 points
Answer: FeO
Explanation:
Answer:
This is not worth 50 points liar
Explanation:
What is the empirical formula for a compound that is comprised of 54.0% sodium, 8.50% boron, and 37.5% oxygen by mass?
A) Na2B2O3.
B) Na3BO3.
C) Na3B2O2.
D) Na4BO4.
Answer:
B) Na3BO3.
Explanation:
Hello!
In this case, since percent compositions are used to identify the empirical formula of an unknown compound, we can assume we have 54.0 g of sodium, 8.50 g of boron and 37.5 g of oxygen, and we compute the moles of each one:
[tex]n_{Na}=54.0g*\frac{1mol}{23g} =2.35mol\\\\n_B=8.50g*\frac{1mol}{11g}=0.773mol\\\\n_O=37.5g*\frac{1mol}{16g}=2.34mol[/tex]
Now, we divide by the moles of boron as those are the fewest:
[tex]Na:\frac{2.35}{0.773}=3\\\\B:\frac{0.773}{0.773}=1\\\\O=\frac{2.34}{0.773}=3[/tex]
Thus, the empirical formula is B) Na3BO3.
Best regards!
Why is it possible for an active metal like aluminum to be useful as a structural metal?
Answer:
Aluminum even after being an active metal is used as a structural metal due to its toughness, high strength, lightweight, and resistance to the process of corrosion. It is resistant to corrosion as its reactivity gets suppressed due to the formation of an aluminum oxide film which is protective in nature, on its surface. Passivation is the term for the formation of the protective coating.
Select the correct answer.
Which equation correctly relates kinetic energy, mass, and velocity?
OA. KE=3m22
OB. KE = mv2
Oc. KE=mu
OD. KE = mv3
Answer:
Ke1/2mv2
Explanation:
Hope this helps
Answer:
KE 1/2 MV2
ExplanationExplanationExplanationExplanation: hope this helps
What is the difference between a purine and a pyrimidine?
Answer: Adenine and guanine are the two purines and cytosine, thymine and uracil are the three pyrimidines. The main difference between purines and pyrimidines is that purines contain a sixmembered nitrogencontaining ring fused to an imidazole ring whereas pyrimidines contain only a sixmembered nitrogencontaining ring. They both are types or categories of nitrogen containing bases present in nuclei acids of DNA and RNA.
Purines are 2 Ring or Carbon Ring, Nitrogen containing bases. That consist of these 2 rings next placed next to each other. These examples include - Adenine and Guanine.
Pyrimidines are 1 or single Ring Nitrogen containing structures. There are 3 nitrogenous bases that are categorized as pyrimidines. Cytosine, Thymine, and Uracil.
When [H+] = 4.0 × 10–9 M in water at 25°C, then
Kw =1.0×10–14.
b. pOH = 7.
c. [H3O+] = [OH–].
d. pH= 7
e. A-D are all correct
Answer:
a. Kw = 1.0 × 10⁻¹⁴
Explanation:
a. Let's consider the self-ionization of water.
2 H₂O(l) ⇄ H₃O⁺(aq) + OH⁻
The ion-product of water (Kw) at 25 °C is:
Kw = [H₃O⁺][OH⁻] = 1.0 × 10⁻¹⁴
c. Considering [H⁺] = [H₃O⁺] = 4.0 × 10⁻⁹ M, the concentration of OH⁻ is:
[OH⁻] = 1.0 × 10⁻¹⁴/[H₃O⁺] = 2.5 × 10⁻⁶ M
b. We can calculate the pOH using the following expression.
pOH = -log [OH⁻] = -log 2.5 × 10⁻⁶ = 5.6
d. We can calculate the pH using the following expression.
pH = -log [H⁺] = -log 4.0 × 10⁻⁹ = 8.4
When [H+] = 4.0 × 10–9 M in water at 25°C, then the [tex]Kw =1.0\times 10^-^1^4.[/tex]
What is dissociation constant?
Kw is the dissociation constant or ionization constant of water.
The self-ionization of water will be
[tex]\rm 2 H_2O(l) = H_3O^+(aq) + OH^-[/tex]
The dissociation constant of the water at 25°C will be
[tex]\rm Kw = [H_3O^+][OH^-] = 1.0 \times 10^-^1^4[/tex]
Thus, the correct option is a. [tex]Kw =1.0\times 10^-^1^4.[/tex]
Learn more about dissociation constant
https://brainly.com/question/3657057
pls that is the picture
A 2.52 L container of oxygen gas at 28.6 °C is heated to 45.9 °C. Assuming that the volume of the container can vary, what is the new volume of the gas?
Answer:
4.04433566 L (433566 repeating)
Explanation:
2.52 is divided by 28.6 is 0.0881118 (881118 repeating). multiply 0.0881118 (881118 repeating) by 45.9 to get 4.04433566 L (433566 repeating).
Which particle has the least mass? Proton, a helium atom, electron, hydrogen atom
Answer:electron
Explanation:
According to the CDC, influenza is a respiratory illness caused by the flu virus. Some of the symptoms include cough, sore throat, muscle aches, and vomiting.
Which statement represents a reasonable claim about the effects of the flu virus on the body’s ability to maintain homeostasis?
A
Influenza affects one major system, which must work to restore homeostasis.
B
Influenza affects one system, but multiple systems must interact in order to restore homeostasis.
C
Influenza affects multiple systems and multiple systems must interact in order to restore homeostasis.
D
Influenza affects one major system and secondary systems, but the major system works to restore homeostasis.
Answer:
B. Influenza affects one system, but multiple systems must interact in order to restore homeostasis.
Explanation:
According to the CDC, influenza is a respiratory illness caused by the flu virus of which some symptoms include cough, sore throat, muscle aches, and vomiting.
The statement that represents a reasonable claim about the effects of the flu virus on the body’s ability to maintain homeostasis is that it affects one system which is the RESPIRATORY SYSTEM but multiple systems must intervene in other to maintain homeostatis.
*Homeostatis is the unique way a human body or organism stabilises its internal state despite the changes on the external.
100
80
100 mL
water vapor
Which statement describes what will happen if a student pushes the plunger
to compress the water vapor?
A. The total number of water particles will increase.
B. The amount of energy in the water particles will decrease.
C. The amount of empty space between the water particles will
decrease
D. The total volume of the water particles will increase
I will mark brainliest
Answer:
Explanation:it is c
Answer:
C The amount of empty space between the water particles will decrease
Explanation:
I just took the quiz, have a nice day!
Reacting 10.0 mL of H2(g) with 10.0 mL of C2H4(g) produces 10.0 mL of C2H6 at 1.5 atm. If the reaction produces 3.1 kJ of heat and the decrease in volume requires the heat surroundings do 7.6 J of work on the gases, what is the change in internal energy of the gases?
Answer:
the change in internal energy of the gases is -3.0924 KJ
Explanation:
The computation of the change in internal energy of the gases is as follows;
Given that
Q = -3.1 KJ
= -3100 J
It is negative as the heat is lost from the mixture
And,
W = + 7.6 J
It is positive as the work is done in the mixture
Now we use the following equation
Delat E = Q + W
= -3100 J + 7.6 J
= -3092.4 J
= -3.0924 KJ
Hence, the change in internal energy of the gases is -3.0924 KJ
i need the answer for this
Answer:
need points
Explanation:
500 grams of an unknown substance gains 23000 J of heat as it is heated from a temperature of 250C to 1250C. Using mathematical computation and the chart below, determine the identity of the unknown substance.
Answer:
The given substance is cast iron.
Explanation:
Given data:
Mass of substance = 50 g
Heat absorbed = 23000 J
Initial temperature = 250°C
Final temperature = 1250°C
Which metal is this = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 1250°C - 250°C
ΔT = 1000°C
23000 j = 50 g ×c ×1000 °C
23000 J = 50,000 g. °C×c
c = 23000 J /50,000 g. °C
c = 0.46 J/g.°C
The given substance is cast iron.
Which molecule/molecular compound is joined by a single covalent bond? O2 or N2 or Br2 or CO2?
Which equation best represents the balanced net ionic equation for the reaction that occurs when aqueous solutions of lithium phosphate and magnesium nitrate are mixed?
Answer:
2 PO₄³⁻(aq) + 3 Mg²⁺(aq) ⇒ Mg₃(PO₄)₂(s)
Explanation:
Let's consider the molecular equation that occurs when aqueous solutions of lithium phosphate and magnesium nitrate are mixed.
2 Li₃PO₄(aq) + 3 Mg(NO₃)₂(aq) ⇒ 6 LiNO₃(aq) + Mg₃(PO₄)₂(s)
The complete ionic equation includes all the ions and insoluble species.
6 Li⁺(aq) + 2 PO₄³⁻(aq) + 3 Mg²⁺(aq) + 6 NO₃⁻(aq) ⇒ 6 Li⁺(aq) + 6 NO₃⁻(aq) + Mg₃(PO₄)₂(s)
The net ionic equation includes only the ions that participate in the reaction and insoluble species.
2 PO₄³⁻(aq) + 3 Mg²⁺(aq) ⇒ Mg₃(PO₄)₂(s)
Most of the elements in the periodic table can be described as:
A. metalloids
B. halogens
c. non-metals
D. metals
The answer would be metals :)
1. What kinds of metals are REALLY reactive? why?
2. What kinds of non-metals are REALLY reactive? why?
3. What group on the periodic table doesn’t react at all? why?
Answer:
1. Alkali metals (group 1)
2. halogens (Group 17)
3. noble gasses (group 18)
Explanation:
1. alkali metals only have one valence electron meaning that they really want to lose that one valence electron to get a full octet.
2. halogens have 7 valence electrons meaning that they just need to gain 1 to get a full octet.
3. Nobel gasses already have a full octet meaning that they don't want to react. (atoms only react to get a full octet)
I hope this helps. Let me know if anything is unclear.
Adaleigh is learning about renewable and non-renewable resources in her science class. She decides to take
a nature walk and makes notes of all the renewable resources that she sees. Which of the following is an
observation that Adaleigh could have made on her walk?
A. The seeds on the ground are going to grow into new trees.
B. The tallest trees had the most seeds around their bases.
C. When trees decay, they could eventually turn into coal.
D. Pine trees are older than oak trees.
Answer:
A. The seeds on the ground are going to grow into new trees.
Explanation:
Trees are renewable resources.
help me pleaseeeeee
Answer:
Arthropod (3)
Annelids (2)
Cnidarians (1)
Echinoderms (4)
Explanations:
I hope all this helps if u don't understand it let me know.