How many milliliters is 0.55 L? O A. 1000 ml OB. 0.00055 mL O C. 550 ml D. 55 mL

tatuchka [14]

Answer:

It is expressed as a multiple of one-twelfth the mass of the carbon-12 atom, 1.992646547 × 10−23 gram, which is assigned an atomic mass of 12 units. ... In this scale 1 atomic mass unit (amu) corresponds to 1.660539040 × 10−24 gram.

6 0

3 years ago

The layer in which all living things on earth live and allows you to breathe is called the?

Ksju [112]

A troposphere because that is where all the CO2 and where we live

6 0

3 years ago

Write the isotopic symbol for the following (show your work) a) An isotope of iodine whose atoms have 78 neutrons b) An isotope

morpeh [17]

Answer:

For a: The isotopic representation of iodine is $_{53}^{131}\textrm{I}$

For b: The isotopic representation of cesium is $_{55}^{137}\textrm{Cs}$

For c: The isotopic representation of strontium is $_{38}^{52}\textrm{Sr}$

Explanation:

The isotopic representation of an atom is: $_Z^A\textrm{X}$

where,

Z = Atomic number of the atom

A = Mass number of the atom

X = Symbol of the atom

For a:

We are given:

Number of neutrons = 78

Atomic number of iodine = 53 = Number of protons

Mass number = 53 + 78 = 131

Thus, the isotopic representation of iodine is $_{53}^{131}\textrm{I}$

For b:

We are given:

Number of neutrons = 82

Atomic number of cesium = 55 = Number of protons

Mass number = 55 + 82 = 137

Thus, the isotopic representation of cesium is $_{55}^{137}\textrm{Cs}$

For c:

We are given:

Number of neutrons = 52

Atomic number of strontium = 38 = Number of protons

Mass number = 38 + 52 = 90

Thus, the isotopic representation of strontium is $_{38}^{52}\textrm{Sr}$

3 0

3 years ago

Find the density of an 8 gram rock if the water in a graduated cylinder rises from 25.0 mL to

Olin [163]

To measure the density of the stone placed in a graduated cylinder let us follow these steps bellow

Measure the volume of water poured into a graduated cylinder
Place the object in the water and remeasure the volume.
The difference between the two volume measurements is the volume of the object.
Divide the mass by the volume to calculate the density of the object.

We know that the formula for density is given as

Given data

Mass = 8gram

Initial Volume of water in cylinder = 25mL

Final Volume of water in cylinder = 29mL

Hence the volume of the rock = 29-25 = 4mL

Therefore the density of the rock = 8/4 = 2 g/mL

Learn more:

brainly.com/question/17336041

6 0

3 years ago

the radioisotope radon-222 has a half-life of 3.8 days. how much of a 65-g sample of radon-222 would be left after approximately

MariettaO [177]

Use the 1st order decay equation
Cfinal=Cinitiale−kt
by filling in and doing the math you will get:

 Cfinal = 1.11 grams Rn-222 after 23 days.

hope this helps

7 0

3 years ago