All categories

3 years ago

Why is mining for coal a long-term concern?

Chemistry

2 answers:

Free_Kalibri [48]3 years ago

8 0

A. Fossil fuels take a very long time to form so we mine it faster than it can replenish.

maw [93]3 years ago

5 0

Answer: I believe its A

Explanation:

You might be interested in

A solid forms when the average energy of a substance's particles

Dahasolnce [82]

<span>Matter is composed of particles that have kinetic energy. Particles with greater kinetic energy tend form liquids or gases due to increased rates of activity of the particles. Particles with lower energy tend to form solids. So, a solid forms when the average energy of a substance's particles decreases.</span>

4 0

4 years ago

Compare The atomic number

gayaneshka [121]

Answer:

They are different ions of the same element.

Explanation:

on Quizlet

8 0

3 years ago

In which of the following are the symbol and name for the ion given correctly?

Andrej [43]

Fe2+:ferrous ion; fe3+ ferric ion are the one which are correctly named(Answer A) Sn2+ are called stannous ion while Sn4+ are known as stannic ions. Pb2+ are called lead (II) ions while Pb4+ are known as lead (IV) ion Co2+ are known was cobalt (II) ions while Co3+ are known as cobalt(IIi) ion.

7 0

3 years ago

Plumbum hydroxide + acid sulphuric = ?

lianna [129]

Answer:

Lead II

Explanation:

PLEASE MARK ME BRAINLIEST

6 0

4 years ago

A. Calculations for the Determination of Ammonium Chloride The data from the data entry portion of the report has been copied in

Vladimir79 [104]

Answer:

Explanation:

Considering question A

Mass of original sample is $m_o = 0.945 \ g$

Mass of NH4Cl is $m_n = 0.116 \ g$

Percent of NH4Cl is $k = 12.275 \%$

Mass of NaCl $m_k = 0.359 \ g$

Mass of SiO2 $m_e = 0.46$

Mass of original sample $m_o = 0.945 \ g$

Differences in these weights (g) (use the absolute value of the difference)

recovery of matter $G = 0.01 \ g$

The correct option is C

From the question we are told that

The mass of evaporating dish on #1 is $m_1 = 38.646 \ g$

The mass of evaporating dish and original sample $m_2 = 39 591 \ g$

The mass of evaporating dish after subliming $NH_4Cl$ is $m_3 = 39.4750 \ g$

Generally the mass of the original sample is mathematically represented as

$m_o = m_2 - m_1$

=> $m_o = 39 591 - 38.646$

=> $m_o = 0.945 \ g$

Generally the mass of $NH_4Cl$ is mathematically represented as

$m_n = m_2 - m_3$

=> $m_n = 39 591 - 39.4750$

=> $m_n = 0.116 \ g$

The Percent $NaH_4 Cl (g)$

$k = \frac{ m_n}{m_o} *100$

=> $k = \frac{0.116 }{0.945} *100$

=> $k = 12.275 \%$

Considering question B

The mass of evaporating dish #2 is $m_g = 38700\ g$

The mass of watch glass is $m_a = 28 299 \ g$

The mass of evaporating dish #2, watch glass and NaCl $m_b = 67,355 \ g$

Generally the mass of NaCl is

$m_k = m_b -[m_g + m_a]$

=> $m_k = 67,355 -[38700 + 28 299]$

=> $m_k = 0.359 \ g$

Considering question C

The mass of evaporating dish is $m_p= 38.645$

The mass of evaporating dish and SiO2 $m_s = 39.105 \ g$

Generally the mass of SiO2 is mathematically represented as

$m_e = 39.105 - 38.645$

=> $m_e = 0.46$

Considering D

The mass of the original sample is $m_o = 0.945 \ g$

Generally the experimental mass recovered (NH_4Cl,NaCl, SiO2 ) is mathematically evaluated as

$M =0.116 + 0.46 + 0.359$

$M = 0.935 \ g$

Generally the differences in these weights (g) of recovery of matter is mathematically represented as.

$G =0.945- 0.935$

=> $G = 0.01 \ g$

While drying the NaCl, the liquid boiled and some splattered out of the evaporating dish, causing the recovered mass to be lower.

6 0

3 years ago