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3 years ago

What is chemical change

Chemistry

1 answer:

Igoryamba3 years ago

8 0

Answer:

Chemical change is a chemical process that occurs when a substance combines with another to create an entirely new substance, this process is also called chemical synthesis

Explanation:

You might be interested in

What are the principal alloy elements of an AISI 4340 steel? How much carbon does it have? Is it hardenable? By what techniques?

amid [387]

Answer:

The principal elements are Iron, Nickel, Chromium

It has 0.37% to 0.43% Carbon

It is hardenable.

It can be hardened by cold working, annealing, quenching.

Explanation:

The chemical composition of AISI 4340 Steel are as follows:

Iron --- 95% to 96%

Nickel --- 1.6% to 2.0%

Chromium --- 0.7% to 0.9%

Manganese --- 0.6% to 0.8%

Carbon --- 0.37% to 0.43%

Molybdenum --- 0.2% to 0.3%

Silicon --- 0.15% to 0.30%

Sulfur --- 0.040%

Phosphorous --- 0.0350%

So, the principal alloy elements from this composition are Iron, Nickel and Chromium

The carbon content in this alloy is 0.37% to 0.43%

Yes, it can be hardened.

It can be Hardened by Cold Working, Annealing or Quenching.

3 0

2 years ago

calculate how many milliliters of 0.142 M NaOH are needed to completely neutralize 21.4 mL of 0.294 M H2C4H4O6.

Flura [38]

Answer:

The answer to your question is 88.7 ml

Explanation:

Data

Volume = ?

Concentration of NaOH = 0.142 M

Volume of H₂C₄H₄O₆ = 21.4 ml

Concentration of H₂C₄H₄O₆ = 0.294 M

Balanced chemical reaction

2 NaOH + H₂C₄H₄O₆ ⇒ Na₂C₄H₄O₆ + 2H₂O

1.- Calculate the moles of H₂C₄H₄O₆

Molarity = moles/volume

Solve for moles

moles = Molarity x volume

Substitution

moles = 0.294 x 21.4/1000

Result

moles = 0.0063

2.- Use proportions to calculate the moles of NaOH

2 moles of NaOH ------------------ 1 moles of H₂C₄H₄O₆

x ------------------ 0.0063 moles

x = (0.0063 x 2) / 1

x = 0.0126 moles of NaOH

3.- Calculate the volume of NaOH

Molarity = moles / volume

Solve for volume

Volume = moles/Molarity

Substitution

Volume = 0.0126/0.142

Result

Volume = 0.088 L or 88.7 ml

3 0

3 years ago

Priscilla was building a circuit that used copper wires to connect a battery to a light bulb. As she connected the final wire fr

algol [13]

Answer:

The voltage or potential difference

Explanation:

What makes current flow in a circuit is the voltage or the potential difference.

This force is supplied by the battery or the mains electrical circuit.

Every circuit requires the voltage to drive current through
When a circuit is complete, the battery is able to overcome any resistance by the generating enough voltage which is the force to drive the current through.

7 0

2 years ago

How do you balance the equation in number one?

AleksAgata [21]

____NaNO3 + ___PbO --> ___Pb(NO3)2 + ___Na[2]O

To balace the eqaution, you need to have the same number of atoms for each element on both the reactant (left) and product (right) side.

To start off, you wanna know the number of atoms in each element on both sides, so take it apart:

[reactants] [product]
Na- 1 Na- 2

N- 1 N- 2(it's 2 because the the subscript [2] is outside of the parenthesis)

O- 4 O- 7 (same reason as above)

Pb- 1 Pb- 1

Na is not balanced out, so add a coefficient to make it the same on both sides.In this case, multiply by 2:

2NaNO3

Now Na is balanced, but the N and O are also effected by this, so they also have to be multiplied by 2 and they become:

Na- 2 Na- 2

N- 2 N- 2 (it balanced out)

O- 7 (coefficient times subscript, plus lone O) O- 7 (balanced out)

Pb was already balanced so no need to mess with it, just put a 1 where needed (it doesn't change anything).

Now to put it back together, it will look like this:

2NaNO3 + 1PbO --> 1Pb(NO3)2 + 1Na[2]O

3 0

3 years ago

A 100.0 lb skier moves at 40.00miles/hour. Calc her kinetic energy.

Pepsi [2]

answer: its 7290 joules.

explanations: the first procedure is to convert 1 pound to kilogram. 1 kg = 2.205 hence given 100 lb so we cross multiply. 1 kg * 100 = 2.205 * x

hence x= 45 kg. let's convert 1 mile per hour = 0.45 metre per second we cross multiply by 40 mile per hour. x= 40 * 0.45= 18 m/s.

KE= 1/2 * 45 * (18)^2

= 1/2 * 45 * 14580

= 7290joules

5 0

3 years ago