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3 years ago

1.

Chemistry

1 answer:

PtichkaEL [24]3 years ago

3 0

Answer:

Hydrogen atoms are fused into deuterium, then helium-3, then helium-4, each step giving off large amounts of energy.

Explanation:

Nuclear fusion refers to the process in which two lighter nuclei combine together to form one heavier nucleus. In the Sun, hydrogen atoms combine and form helium. This process releases large amounts of energy because the helium atom has less energy than the hydrogen atoms.

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Why are baking directions on cake mix boxes different for higher altitudes

Blababa [14]

Answer:

Explanation:First, the dry air at high elevations tends to make things dry out quickly. Second, the boiling point of water is lower at altitude, which means that moisture will tend to bake out of your cakes more quickly. ... In the reduced air pressure of high altitudes, your leavening ingredients will act more powerfully.

7 0

3 years ago

mixture of N 2 And H2 Gases weighs 13.22 g and occupies a volume of 24.62 L at 300 K and 1.00 atm.Calculate the mass percent of

anygoal [31]

Answer: The mass percent of nitrogen gas and hydrogen gas is 91.41 % and 8.59 % respectively.

Explanation:

To calculate the number of moles, we use the equation given by ideal gas equation:

PV = nRT

where,

P = Pressure of the gaseous mixture = 1.00 atm

V = Volume of the gaseous mixture = 24.62 L

n = number of moles of the gaseous mixture = ?

R = Gas constant = $0.0821\text{ L atm }mol^{-1}K^{-1}$

T = Temperature of the gaseous mixture = 300 K

Putting values in above equation, we get:

$1.00atm\times 24.62L=n_{mix}\times 0.0821\text{ L atm }mol^{-1}K^{-1}\times 300K\\\\n_{mix}=\frac{1.00\times 24.62}{0.0821\times 300}=0.9996mol$

We are given:

Total mass of the mixture = 13.22 grams

Let the mass of nitrogen gas be 'x' grams and that of hydrogen gas be '(13.22 - x)' grams

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

For nitrogen gas:

Molar mass of nitrogen gas = 28 g/mol

$\text{Moles of nitrogen gas}=\frac{x}{28}mol$

For hydrogen gas:

Molar mass of hydrogen gas = 2 g/mol

$\text{Moles of hydrogen gas}=\frac{(13.22-x)}{2}mol$

Equating the moles of the individual gases to the moles of mixture:

$0.9996=\frac{x}{28}+\frac{(13.22-x)}{2}\\\\x=12.084g$

To calculate the mass percentage of substance in mixture we use the equation:

$\text{Mass percent of substance}=\frac{\text{Mass of substance}}{\text{Mass of mixture}}\times 100$

Mass of the mixture = 13.22 g

For nitrogen gas:

Mass of nitrogen gas = x = 12.084 g

Putting values in above equation, we get:

$\text{Mass percent of nitrogen gas}=\frac{12.084g}{13.22g}\times 100=91.41\%$

For hydrogen gas:

Mass of hydrogen gas = (13.22 - x) = (13.22 - 12.084) g = 1.136 g

Putting values in above equation, we get:

$\text{Mass percent of hydrogen gas}=\frac{1.136g}{13.22g}\times 100=8.59\%$

Hence, the mass percent of nitrogen gas and hydrogen gas is 91.41 % and 8.59 % respectively.

5 0

3 years ago

Which law is associated with inertia? *

defon

Newton first law of motion

Explanation:

This law by Newton states that an object will remain at rest, or a moving object will stay in motion in a straight line and with the same speed unless an external and unbalanced force acts on the object.

One application of this Newtonian law is in the launching of projectiles like ballistic missiles. A ballistic missile parabolic path is affected by its inertia and the unbalanced forces acting on the object such as air resistance/ drag and gravity.

4 0

3 years ago

If element A is in Group 13 and element B is in Group 17, which ions will be formed when A and B react together?

Kobotan [32]

Answer:

A3+ and B-

Explanation:

Elements in group 13 have outermost electron configuration, ns2np1 hence they form trivalent positive ions.

Elements in group 17 have outermost electron configuration ns2np5 hence they form univalent negative ions.

This implies that, if element A is in Group 13 and element B is in Group 17, the ions formed are A3+ and B-.

8 0

3 years ago

The solubility product constant of pbcl2 is 1.7 × 10−5 . what is the maximum concentration of pb2+ that can be in ocean water th

Sunny_sXe [5.5K]

Answer is: the maximum concentration of Pb²⁺ is 6.8·10⁻³ M.
Chemical reaction 1: PbCl₂(s) → Pb²⁺(aq) + 2Cl⁻(aq).
Chemical reaction 2: NaCl(aq) → Na⁺(aq) + Cl⁻(aq).
Ksp(PbCl₂) = 1.7·10⁻⁵.
c(NaCl) = c(Cl⁻) = 0.0500 M.
Ksp(PbCl₂) = c(Pb²⁺) · c(Cl⁻)².
c(Pb²⁺) = Ksp(PbCl₂) ÷ c(Cl⁻)².
c(Pb²⁺) = 1.7·10⁻⁵ M³ ÷ (0.0500 M)².
c(Pb²⁺) = 0.000017 M³ ÷ 0.0025 M².
c(Pb²⁺) = 0.0068 M = 6.8·10⁻³ M.

3 0

3 years ago