Answer: There are 
atoms of hydrogen are present in 40g of urea, 
.
Explanation:
Given: Mass of urea = 40 g
Number of moles is the mass of substance divided by its molar mass.
First, moles of urea (molar mass = 60 g/mol) are calculated as follows.
According to the mole concept, 1 mole of every substance contains 
atoms.
So, the number of atoms present in 0.67 moles are as follows.
In a molecule of urea there are 4 hydrogen atoms. Hence, number of hydrogen atoms present in 40 g of urea is as follows.
Thus, we can conclude that there are atoms of hydrogen are present in 40g of urea, .
Reactivity of non-metals depend on their ability to gain electrons. So, smaller is the size of a non-metal more readily it will attract electrons because then nucleus will be more closer to valence shell. ... Hence, Br is the non-metal which will be more reactive than At.
Answer:
The valence electrons in the metal atom in the lattice structure can delocalize and move freely. The electrons are "loosely" connected with their parent atom in the metallic bond because most metals have excess electrons in their outer orbitals above the stable configuration.
Explanation:
Says google
Answer:
A, C, and D
Explanation:
A-Any type of rock can change into any other type of rock by weathering and erosion.
C-Rocks change slowly over time.
D- The rock cycle shows how the three rock types relate to one another.
Its correct on edge
