Answer:
Explanation:
We usually approximate the density of water to about 
at room temperature. In terms of the precise density of water, this is not the case, however, as density is temperature-dependent.
The density of water decreases with an increase in temperature after the peak point of its density. The same trend might be spotted if the temperature of water is decreased from the peak point.
This peak point at which the density of water has the greatest value is usually approximated to about 
. For your information, I'm attaching the graph illustrating the function of the density of water against temperature where you could clearly indicate the maximum point.
To a higher precision, the density of water has a maximum value at , and the density at this point is exactly .
If it’s multiple answers then it’s A,C,D. If it’s only one answer then your best answer is A. Because you always report accidents to an authority so that they can figure out how to solve the problem.
Answer: 4.21×10⁻⁸
Explanation:
1) Assume a general equation for the ionization of the weak acid:
Let HA be the weak acid, then the ionization equation is:
HA ⇄ H⁺ + A⁻
2) Then, the expression for the ionization constant is:
Ka = [H⁺][A⁻] / [HA]
There, [H⁺] = [A⁻], and [HA] = 0.150 M (data given)
3) So, you need to determine [H⁺] which you do from the pH.
By definition, pH = - log [H⁺]
And from the data given pH = 4.1
⇒ 4.10 = - log [H⁺] ⇒ [H⁺] = antilog (- 4.10) = 7.94×10⁻⁵
4) Now you have all the values to calculate the expression for Ka:
ka = 7.94×10⁻⁵ × 7.94×10⁻⁵ / 0.150 = 4.21×10⁻⁸
The nucleus of an atom contain neutrons and protons, and energy levels surround the nucleus, in rings and contain electrons
Answer:
Empirical formula is CH₄
Molecular formula = C₂H₈
Explanation:
Mass of carbon = 37.5 g
Mass of hydrogen = 12.5 g
Molecular weight = 32 g/mol
Molecular formula = ?
Empirical formula = ?
Solution:
Number of gram atoms of C = 37.5 g /12g/mol = 3.125
Number of gram atoms of H = 12.5 g / 1.008 g/mol= 12.4
Atomic ratio:
C : H
3.125/3.125 : 12.4 /3.125
1 : 4
C : H : = 1 : 4
Empirical formula is CH₄
Molecular formula:
Molecular formula = n (empirical formula)
n = molar mass of compound / empirical formula mass
n = 32 / 16
n = 2
Molecular formula = n (empirical formula)
Molecular formula = 2 ( CH₄)
Molecular formula = C₂H₈
