Answer:
Q = -627.6 J
Explanation:
Mass, m = 15 grams
Initial temperature, [tex]T_i=40^{\circ} C[/tex]
Final temperature, [tex]T_f=30^{\circ} C[/tex]
We need to find the amount of heat released by this much of sample of water. We know that heat released is given by the below formula :
[tex]Q=mc\Delta T[/tex]
c is specific heat of water, [tex]c=4.184\ J/g-K[/tex]
[tex]\Delta T=T_f-T_i\\\\=(30^{\circ}-40^{\circ} )\ C\\\\=-10^{\circ} C\\\\=-10\ K[/tex]
So,
[tex]Q=15\times 4.184\times -10\\\\Q=-627.6\ J[/tex]
Hence, 627.6 J of heat is released and negative sign shows that energy is being given off.
#8- please help i suck at this, ill mark brainliest
Answer:
A. Synthesis
B. Combustion
C. Single-replacement
D. Decomposition
Explanation:
A: Synthesis. Two reactants are combined to form, or synthesize, one product.
B: Combustion. This is the general reaction for combustion. When something combusts, oxygen must be present. Carbon dioxide and water must also be produced.
C: Single-replacement. The oxygen from Fe₂O₃ is moved to K to form K₂O. Only one thing is being moved, or replaced.
D: Decomposition. You have one compound that breaks into, or decomposes, into two products.
#7- pls help me ill mark you brainliest and ill give you 5 stars <3
Answer:
I think it is synthesis
Answer:
The answer is Synthesis
Explanation:
The two objects combine to make a bigger object
what is the cell cycle? plz help, ASAP
Answer:
It is the process of events that happen in a cell before the cell division occurs. Please see the attached image for a better clarification of the cell cycle.
Explanation:
Explain why the several different types of microscopes are all necessary.
Answer:
some zoom in farther
Explanation:
some microscopes zoom in farther than others so we can see even smaller things
Can someone please help me
Can an Atom be broken down into a smaller substance? Yes or No Explain.
Answer:
Yes
Explanation:
A atom is made out of 3 elements, protons which are positive charges, electrons which are negative charges that swirl around the atom, and a neutron with a neutral charge. The nucleus of the atom is basically the center of the atom.
What is the difference between the crest and the trough of a wave?
Answer:
Trough is the lower bound of wave, while the crest is the upper bound of a wave.
Explanation:
see picture attatched
Which of the following elements has the largest electronegativity? A) Bismuth B) Nitrogen C) Potassium D) Arsenic
This illustration is an example of a
The illustration is an example of surface waves.
Match each description to a type of radiation Drag each item to the appropriate bin.
Answer:
Explanation:
Beta radiations:
mass 1/200 , charge -1, medium penetration
Beta radiations are result from the beta decay in which electron is ejected.
The mass of beta particle is smaller than the alpha particles.
They can travel in air in few meter distance.
These radiations can penetrate into the human skin.
The sheet of aluminum is used to block the beta radiation
Properties of alpha radiation:
mass 4 amu, charge +2, least penetration
Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number less than 4 and atomic number less than 2 as compared to parent atom the starting atom.
Alpha radiations can travel in a short distance.
These radiations can not penetrate into the skin or clothes.
These radiations can be harmful for the human if these are inhaled.
These radiations can be stopped by a piece of paper.
Gamma radiations:
mass 0, charge 0, deepest penetration
Gamma radiations are high energy radiations having no mass.
These radiations are travel at the speed of light.
Gamma radiations can penetrate into the many materials.
These radiations are also used to treat the cancer.
Lead is used for the protection against gamma radiations because of its high molecular density.
The lead apron are used by the person when treated with gamma radiations.
Which types of reactions would result in the formation of precipitate?
Answer:
Double Displacement Reaction
Explanation:
A double displacement reaction is a type of chemical reaction in which the reactant ions exchange places to form new products. Usually, a double displacement reaction results in precipitate formation.
Choose all the answers that apply. lonic compounds ___.
A. do not dissolve in water
B. have high melting points
C. have low melting points
D.dissolve easily in water
E. conduct electricity when melted
(science class not chemistry)
Answer:
E conduct electricity when melted
Explanation:
They can not produce electricity until dissolved/ melted in water
3. Which of the following is NOT an abiotic factor in an ecosystem?
Air pressure
Bacteria
Sunlight
Water
pls help ill mark you as brainliest
Answer:
Explanation:
Synthesis- D
Combustion- C
Decomposition- A
Single Displacement- C
Double Displacement- B
Parts of mixture
a / can not be separated
b/ have new properties after they are mixed
C/ form achemicl combination of two or more atoms
Answer:
B- Have new properties after they are mixed
I hope this helps
Classify the following reactions and complete the given below
A) NaCl + AgNO3 - NaNO3 + AgCl
Answer:
chemical equation balance.
Explanation:
if you need more explanation , comment.
What will the coefficients be for the following balanced equation? (a) N2 + (b) H2 → (c) NH3
Answer:
his reaction is the synthesis of Ammonia using Nitrogen and Hydrogen gas.
N
+
H
→
N
H
3
We must remember that Nitrogen and Hydrogen are both diatomic molecules in their standard gas form. This adjusts the equation to
N
2
+
H
2
→
N
H
3
Now we need to adjust coefficients in order to balance the atoms on each side of the equation. Currently we have 2 atoms of nitrogen and 2 atoms of hydrogen on the reactant side and 1 atom of nitrogen and 3 atoms of hydrogen on the product side.
We can balance the hydrogens by placing a coefficient of 2 in front of ammonia and a coefficient of 3 in front of the hydrogen.
N
2
+
3
H
2
→
2
N
H
3
This gives us 6 hydrogen on each side and coincidentally the nitrogens now equal 2 on each side.
I hope this was helpful.
Explanation:
Answer:
1N2 + 3H2 →2NH3
Explanation:
Plato answer
What are two properties of most nonmetals
Answer: Summary of Common Properties
High ionization energies.High electronegativities.Poor thermal conductors.Poor electrical conductors.Brittle solids—not malleable or ductile.Little or no metallic luster.Gain electrons easily.Dull, not metallic-shiny, although they may be colorful.Explanation:
May I please have brainiest?
Answer:
The two properties of most non metals are high ionization energy and poor electrical conductivity. The correct option among all the options that are given in the question is option "1". In general it is known that nonmetals are very poor conductors of heat and electricity. The nonmetals that are solid are normally very brittle and has very little or no metallic luster at all. Nonmetals are highly reactive and show variety of chemical properties. It can also be pointed out that the nonmetals gain electrons very easily.
brainliest pleaseee :)
Multiple choice!
:D god
PLZ HELP ME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
Reactivity
Explanation:
Luster. Ductile, and Malleabillity are all physical.
Order the masses from smallest to largest
Can someone please tell me if this right.
Answer:
1. 7.86 × 10⁴ g
2. 7.86 × 10⁴ kg
3. 1.989 × 10¹³ mg
4. 1.989 × 10²⁸ kg
5. 1.989 × 10³³ g
Explanation:
The easiest way to make sure you have the right answer is to convert all units to the same unit.
A. 1.989 × 10¹³ mg = 1.989 × 10¹⁰ g
B. 7.86 × 10⁴ g
C. 1.989 × 10³³ g
D. 7.86 × 10⁴ kg = 7.86 × 10⁷ g
E. 1.989 × 10²⁸ kg = 1.989 × 10³¹
The correct order is B < D < A < E < C
Joe bought a roll of gray duct tape containing 5400 inches. If there are 5280 feet in a mile, how
many miles long is Joe's roll of duct tape?
Answer:
STANDARD: 0.085 mi, 450 ft, or 150 yds
METRIC: 0.137 km, 137.16 m, or 13716 cm
Explanation:
Assume that the pendulum clock shown in the photograph is a closed
system
Which statement describes evidence that the pendulum's energy is conserved
even as it eventually stops moving?
A. Energy must be added to the pendulum to keep it from slowing
down
B. Some of the clock's matter is transformed into new energy
C. The amount of each type of energy in the system can be
measured
D. All its mechanical energy is transformed into other forms of
energy
Answer:
Explanation:
d
Answer:
D. All it’s mechanical energy is transformed into other forms of energy.
Explanation:
I got it right
What is true about ionic compounds?
Select all that apply.
A. Properties of the compound are different than the properties of individual atoms that make the compound.
B. Electrons are not involved in the formation of an ionic bond, since ions do not have valence electrons.
C. Electrons are not free to move.
D. They may have a positive or negative charge.
The ___ has many functions; one is to regulate growth.
Growth hormon somatotropin
A 0.2027 gram sample of finely powdered limestone (mainly CaCO₃) was dissolved in 50 mL of 0.1035 M HCl. The solution was heated to expel CO₂ produced by the reaction. The remaining HCl was then titrated with 0.1018M of NaOH and it required 16.62 mL. Calculate the percentage of CaCO₃ in the limestone sample? CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
Answer:
Explanation:
CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
100 gm + 2000 mL of M HCl
Amount of HCl remaining = .1018 M of 16.62 mL
= .1018 x 16.62 mL of M HCl
= 1.69 mL of M HCl
Initial HCl taken = 50 mL of .1035 M HCl
= 5.175 mL of M HCl
HCl reacted = 5.175 - 1.69 mL of M HCl
= 3.485 mL of M HCl
2000 mL of M HCl reacts with 100 gm of CaCO₃
3.485 mL of M HCl will react with .174 grams of CaCO₃
percentage of calcium carbonate = .174 x 100 / .2027
= 85.84 %
How many minutes are In 3,417 seconds?
Answer:
57 minutes and 35 seconds, or 56.95
Explanation:
Answer:
56.95 minutes
Explanation:
hope it helps
Someone drops a book on the floor, and it makes a loud noise. At that time, you turn to look at the person who dropped the book. Turning and looking at the person who dropped the book is an example of a…
A. Phototropism
B. Response
C. Hydrotropism
D. Stimulus
Answer:
D
Explanation:
Plastic, rocks, rabbits and steel are all made of matter. Matter is made up of tiny particles called ________.
Question 1 options:
a nucleus
atoms
energy
molecules
Answer:
atoms should be the correct answer
Answer:
Matter is made up of tiny particles called atoms.
Explanation:
Atoms are made up of protons, neutrons and electrons. Atoms come together to form molecules which are building blocks for all types of matter.
Answer question number 3