Answer : The correct option is, (B) 
Solution :
According to the Graham's law, the rate of effusion of gas is inversely proportional to the square root of the molar mass of gas.

or,
..........(1)
where,
= rate of effusion of unknown gas = 
= rate of effusion of oxygen gas = 
= molar mass of unknown gas = ?
= molar mass of oxygen gas = 32 g/mole
Now put all the given values in the above formula 1, we get:


The unknown gas could be carbon dioxide
that has approximately 44 g/mole of molar mass.
Thus, the unknown gas could be carbon dioxide 
A solid-state<span> phase </span>transformation<span> occurs when the interface between two grains that are chemically or structurally different moves.</span>
<h2>The isotopes of an element all have the same __(atomic, mass) __number, but they have different __(atomic,mass)__numbers.</h2>
Explanation:
The isotopes of an element all have the same __atomic number __, but they have different __mass __numbers.
The isotopes have same atomic number that is :
- Same number of electrons
- Same number of protons
- same electronic configuration
- same valence electrons
- same valency
- same symbol
The isotopes have different mass number that is :
They differ in number of neutrons .
For example : Isotopes of hydrogen are : H₁¹ , H₁² , H₁³
isotopes of Oxygen is : O¹⁶ , O¹⁷, O¹⁸
Answer:
Fossils are remains or traces from ancient life's that is most likely buried in rocks anywhere in the world. Fossils are basically bones, teeth, shells, nests, leaf impressions, and footprints. That is technically explaining what our planet was like long ago. Some dinosaur fossils have been found. Paleontologists find them almost everywhere. If you don't know what Paleontologists are, they're basically people who study fossils. A lot of fossils are found in sedimentary rocks. Sedimentary is a rock that has been formed from things like sand, mud, and many other kinds of rocks.
Hope this helps.
Answer:
Although the story of Beowulf is set in Scandinavia what language was it written in Old English.
Explanation:
Beowulf is a very old piece of literary genre. It is one of the earliest European epic written in vernacular language. It is an epic poem written in old English. The setting of the story has been set in Scandinavia. Beowulf is the hero of the poem. He is the protagonist of the story who survives the attacks of the monster named Grendel.