Answer:
C) A lion preys on a herd of gazelle.
Explanation:
That there was a dense positively charged center, what we call the nucleus now.
Answer:
CaC2 + 2H20 ⇋Ca(OH)2 + C2H2
Explanation:
CaC2 + A H20 ---> Ca(OH)2 + A C2H2
This is calcium carbide reacting with water to produce calcium hydroxide and ethyne commonly called acetylene.
Let's now balance the equation.
CaC2 + 2H20 ⇋Ca(OH)2 + C2H2
Answer:
The correct answer is - C) 3 hours.
Explanation:
Given:
The half-life = 1 hour
Solution:
The half-life of an element is the time required to decay half of its initial amount.
To complete 87.5%, there total numbers of half-live would be -
1st halflife = 50% of the initial amount
2nd half-life = 50 + 50% of (50) = 50 +25 = 75% of initial amount
3rd half-life = 50 + 50 % of (50) + 50% of (25) = 87.5% of initial amount
so, to complete the 87.5 % of decay it required 3 half lives, and each half-life take one hour thus, total time taken = 3 hours
Given that,
The equation is : 
To find,
The missing coefficients.
Solution,
Let the value of ? is x.
It is the equation of photosynthesis.
In LHS,
Carbon atoms = 6
Hydrogen atom = 12
Oxygen atom = 18
In RHS,
Carbon atoms = 6
Hydrogen atom = 12
Oxygen atom = 6
If we make the equation as 
No the number of atoms in RHS = 6+ 12 = 18
It means if we take the value of ? as 6 the equation will be balanced.
Hence, the correct option is (B) "6".
