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Murljashka [212]

2 years ago

14

Which activity is an example of chemical change?

1 answer:

frutty [35]2 years ago

3 0

An old penny rusting, remember you can’t undo a chemical change

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In the molecule of SO2 there are two pie bonds these are formed Due to

Aleks [24]

These are formed when, after formation of the first atom, the pi-orbitals of Sulfur and Oxygen align and share another pair of electrons. This occurs between sulfur and both of the oxygen atoms, with each oxygen atom forming one pi-bond.

4 0

3 years ago

There is a photon with a frequency of 8x10^12 Hz. What is the energy of this<br> photon?

jarptica [38.1K]

Answer:

33.085476 meV ≈ 33 meV

Explanation:

Hope this helped!

7 0

2 years ago

Which statement about fusion reactors is true? a Enriched uranium isotopes are used as fuel in fusion reactors. b Fuel for fusio

trapecia [35]

Answer:

b Fuel for fusion reactors can be extracted from ocean water.

Explanation:

The fuel is deuterium, which makes up 0.02% of the hydrogen atoms in water. The oceans contain more than a billion cubic kilometres of water, so that's a lot of deuterium.

a is wrong. The fuel for fusion reactors is deuterium.

c is wrong. There is much research, but there are no large-scale fusion reactors in operation.

d is wrong. Fusion reactors do not produce radioactive waste as spent fuel. Most of the radioactive waste would be the reactor core itself.

6 0

2 years ago

g Five calcite, CaCO3 (MW 100.085 g/mol), samples of equal mass have a total mass of 12.3±0.1 g. What is the absolute uncertaint

diamong [38]

Answer:

The value is $L = 0.985 \pm 0.00801 \ g$

Explanation:

From the question we are told that

The molar mass of $CaCO_3$ is $MW = 100.085 \ g/mol$

The total mass is $m_g = 12.3 \ g$

The uncertainty of the total mass is $\Delta g = 0.1$

Generally the molar weight of calcium is $M_c = 40 g/mol$

The percentage of calcium in calcite is mathematically represented as

$C = \frac{40.07}{100.085} * 100$

$C = 40.03 \%$

Generally the mass of each sample is mathematically represented as

$m= \frac{m_g}{5}$

$m= \frac{12.3}{5}$

$m= 2.46 \ g$

Generally mass of calcium present in a single sample is mathematically represented as

$m_c = 2.46 * \frac{40.04}{100}$

$m_c = 0.985 \ g$

The uncertainty of mass of a single sample is mathematically represented as

$k = \frac{\Delta g }{5}$

$k = \frac{0.1 }{5}$

$k = 0.02\ g$

The uncertainty of mass of calcium in a single sample is mathematically represent

$G = \frac{0.02 * 40.04}{ 100}$

$G = 0.00801 \ g$

Generally the average mass of calcium in each sample is

$L = 0.985 \pm 0.00801$

6 0

2 years ago

In which state of matter are the particles at rest (not moving at all)?

Sidana [21]

Answer:

Solids for sure

particles of solid cant flow.

8 0

2 years ago

Read 2 more answers