Answer:
Empirical formula is Cr₂O₃.
Explanation:
Given data:
Percentage of Cr = 68.4%
Percentage of O = 31.6%
Empirical formula = ?
Solution:
Number of gram atoms of Cr = 68.4 / 52 = 1.3
2
Number of gram atoms of O = 31.6 / 16 = 1.98
Atomic ratio:
Cr : O
1.32/1.32 : 1.98/1.32
1 : 1.5
Cr : O = 1 : 1.5
Cr : O = 2(1 : 1.5)
Empirical formula is Cr₂O₃.
<h3>
Answer:</h3>
Fe₂O₃(s) + 3CO(g) → 2Fe(s) + 3CO₂(g)
<h3>
Explanation:</h3>
Concept tested: Balancing of chemical equations
- A chemical equation is balanced by putting appropriate coefficients on the products and reactants of the equation.
- Balancing chemical equations ensures that chemical equations obey law of conservation of mass.
- In this case; to balance the above equation we put the coefficients, 1, 3, 2, and 3 on the reactants and products.
- Therefore; the balanced chemical equation for the reaction is;
Fe₂O₃(s) + 3CO(g) → 2Fe(s) + 3CO₂(g)
Answer:
it depends upon a his body which antigen is present
Explanation:
it depends on that person not on their parents
Answer:
Answers are in the explanation
Explanation:
Equlibrium of HF in H₂O is:
HF + H₂O ⇄ F⁻ + H₃O⁺
Now, the KOH reacts with HF, thus:
KOH + HF → F⁻ + H₂O
<em>That means after reaction, concentration of HF decrease increasing F⁻ concentration.</em>
Now, seeing the equilibrium, as moles of HF decrease and F⁻ moles increase, the equilibrium will shift to the left decreasing H₃O⁺ concentration.
For the statements:
A. The number of moles of HF will increase. <em>FALSE</em>. HF react with KOH, thus, moles of HF decrease
B. The number of moles of F- will decrease. <em>FALSE</em>. The reaction produce F⁻ increasing its moles.
C. The equilibrium concentration of H₃O⁺ will increase. <em>FALSE. </em>The equilibrium shift to the left decreasing concentration of H₃O⁺
D. The pH will decrease. <em>FALSE</em>. As the H₃O⁺ concentration decrease, pH will increase
E. The ratio of [HF] / [F-] will remain the same. <em>FALSE</em>. Because moles of HF are decreasing whereas F- moles are increasing changing, thus, ratio.
Answer:- 3. 
and 
Explanations:- An empirical formula is the simplest whole number ratio of atoms of each element present in the molecule/compound.
For example, the molecular formula of benzene is 
. The ratio of C to H in it is 6:6 that could be simplified to 1:1. So, an empirical formula of benzene is CH.
In the first pair, the ratio of C to H in first molecule is 2:4 that could be simplified to 1:2 and the empirical formula is 
. In second molecule the ratio of C to H is 6:6 and it could be simplified to 1:1. and the empirical formula is CH. Empirical formulas are different for both the molecules of first pair and so it is not the right choice.
In second pair, C to H ratio in first molecule is 1:2, so the empirical formula is . The C to H ratio for second molecule is 1:4, so the empirical formula is 
. Here also, the empirical formulas are not same and hence it is also not the right choice.
In third pair, C to H ratio in first molecule is 1:3, so the empirical formula is . In second molecule the C to H ratio is 2:6 and it is simplified to 1:3. So, the empirical formula for this one is also . Hence. this is the correct choice.
In fourth pair, first molecule empirical formula is CH. Second molecule has 2:4 that is 1:2 mole ratio of C to H and so its empirical formula is . As the empirical formulas are different, it is not the right choice.
So, the only and only correct pair is the third one. 3. and
