Answer:
I think it's A
Explanation:
I'm sorry if it's not correct. I'm tryna get enough points to ask my question
0.212 g of KHP is are dissolved in 50.00 mL of water and are titrated by 35.00 mL of 0.0297 M NaOH.
Potassium hydrogen phthalate, KHP, is a monoprotic acid often used to standardize NaOH solutions.
The balanced neutralization equation is:
NaOH(aq) + KHC₈H₄O₄(aq) ⇒ KNaC₈H₄O₄(aq) + H₂O(l)
- Step 1: Calculate the reacting moles of KHP.
0.212 g of KHP react. The molar mass of KHP is 204.22 g/mol.
0.212 g × 1 mol/204.22 g = 1.04 × 10⁻³ mol
- Step 2: Determine the reacting moles of NaOH.
The molar ratio of NaOH to KHP is 1:1.
1.04 × 10⁻³ mol KHP × 1 mol NaOH/1 mol KHP = 1.04 × 10⁻³ mol NaOH
- Step 3: Calculate the molarity of NaOH.
1.04 × 10⁻³ moles of NaOH are in 35.00 mL of solution.
[NaOH] = 1.04 × 10⁻³ mol / 35.00 × 10⁻³ L = 0.0297 M
0.212 g of KHP is are dissolved in 50.00 mL of water and are titrated by 35.00 mL of 0.0297 M NaOH.
Learn more about titration here: brainly.com/question/4225093
A chemical change affects on the molecular level of matter, which makes it irreversible. Combustion is a pretty good exmple. Physical changes are reversible and dont alter the formula. Hope this helped!
Answer:
Zn, Cu, Fe, Mn, Co, Mo
Explanation:
Biogenic elements are chemical elements constantly present in organisms and having definite biological significance(Bowen, 1966).
There are many of these biogenic elements in nature. Among the elements of the d-block, Zn, Cu, Fe, Mn, Co, Mo are worthy of mention among others.
Free ions of d- block metals are not found in the body. The elements are present in the form of bioinorganic complexes of the respective metals. They commonly exist as co-factors of proteins that carry out essential biological functions.
Answer:
0.4444 g/cm³ ≅ 0.44 g/cm³ (2 significant figures).
Explanation:
<em>d = m/V,</em>
where, d is the density of the material (g/cm³).
m is the mass of the material (m = 28 g).
V is the volume of the material (V = 63.0 cm³).
<em>∴ d = m/V </em>= (28 g)/(63.0 cm³) = <em>0.4444 g/cm³ ≅ 0.44 g/cm³ (2 significant figures).</em>