Ask question

Ask question

All categories

Ira Lisetskai [31]

3 years ago

15

If atoms are so tiny how do we know they exist

1 answer:

Aleksandr [31]3 years ago

5 0

There are three ways that scientists have proved that these sub-atomic particles exist. They are direct observation, indirect observation or inferred presence and predictions from theory or conjecture. Scientists in the 1800's were able to infer a lot about the sub-atomic world from chemistry.

You might be interested in

A 19-g piece of metal absorbs 186.75 joules of heat energy, and its temperature changes from 35°C to 175°C. Calculate the specif

slavikrds [6]

Answer:

0.0702J/g°C the specific heat capacity of the metal.

Explanation:m

$Q=m\times c\times \Delta T=m\times c\times (T_{2}-T_{1})$

where,

Q = heat absorbed by metal = 186.75 J

$m_1$ = Mass of metal= 19 g

$T_1$ = Initial temperature of metal = $35^oC$

$T_2$ =Final temperature of metal = $175^oC$

$c$ = specific heat of metal= ?

$186.75 J=19 g\times c\times (175^oC-35^oC)$

$c=\frac{186.75 J}{19 g\times (175^oC-35^oC)}$

$c=0.0702J/g^oC$

0.0702J/g°C the specific heat capacity of the metal.

6 0

3 years ago

Set up the math. But don’t do any of it. Just leave your answer as a math expression. Also be should you’re answering includes a

andreev551 [17]

Answer:

See below

Explanation:

9 m * 2.16 kg/ m = ___________ kg ( see how the 'm' cancels out?)

4 0

2 years ago

What mass of iron(III) oxide will be formed if 9.30 L of oxygen at STP react with excess iron?

iragen [17]

Answer:

12

Explanation:

because that plot and the iron

4 0

3 years ago

A certain element exists as two different isotopes. 90.50% of its atoms have a mass of 20.00 amu and 9.500% of its atoms have a

Serga [27]

Answer:

20.19 amu.

Explanation:

From the question given above, the following data were obtained:

Isotope A:

Abundance (A%) = 90.5%

Mass of A = 20 amu

Isotope B:

Abundance (B%) = 9.5%

Mass of B = 22 amu

Average atomic mass =..?

The average atomic mass of the element can be obtained as follow:

Average atomic mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100]

Average atomic mass = [(20 × 90.5)/100] + [(22 × 9.5)/100]

Average atomic mass = 18.1 + 2.09

Average atomic mass = 20.19 amu

Therefore, the average atomic mass of the element is 20.19 amu

6 0

3 years ago

An indicator is what type of compound?<br> pls helppp

denpristay [2]

Indicators are colorful compounds that are weak acids or bases.

3 0

3 years ago