In a hexagonal-close-pack (hcp) unit cell, the ratio of lattice points to octahedral holes to tetrahedral holes is 1:1:2. What i

B The two substances exhibit distinct physical and chemical characteristics, even though they are both composed of nitrogen and oxygen.

We are tasked with determining the heat required to elevate the temperature of water from 85.0 ⁰F to 50.4 ⁰F.

To increase the temperature from 50.4 ⁰F to 85.0 ⁰F, a heat amount of 10.857 kJ is necessary.

The needed heat for the temperature increase can be calculated using the equation H = m×s×(t₂-t₁).

In this equation, H is the heat, s represents specific gravity at 4.184 J/g.⁰C, m is the mass of 135.0 g, t₁ (the initial temperature) is 50.4 ⁰F or 10.222 ⁰C, and t₂ (final temperature) stands at 85.0⁰F or 29.444 ⁰C.

After inputting these values, we find:

H = 135.0 g × 4.184 J/g.⁰C × (29.444 - 10.222) ⁰C

Simplifying gives us H = 10857.354 J or 10.857 kJ.

Thus, to elevate the temperature, 10857.354 J or 10.857 kJ of heat is necessary.

From the table presented, C₆H₅O⁻ is the most frequently attached to the acidic hydrogen, due to its lower Ka (<span>acid dissociation constant). Chemical reaction: C₆H₅OH(aq) ⇄ C₆H₅O⁻(aq) + H⁺(aq). Ka = [C₆H₅O⁻] · [H⁺] / [C₆H₅OH]. The concentration of hydrogen ions in a phenol-water solution is very low.</span>

Answer:

C₄F₈

Explanation:

To find the mass, we will use the mole ratio.

The molar mass of carbon is 12.0107 g/mol.

For fluorine gas, the molar mass is 37.99681 g/mol.

Let x represent the mass of carbon.

The provided mass of fluorine is 1.70 g.

Setting up the proportion: x / 12.01067 = 1.70 / 37.99687.

Now, we will cross-multiply.

This results in: x = (1.70 × 12) / 37.99687 = 20.4 / 37.99687 = 0.53688 g.

To find the mass of one mole of CF₂, we add: 0.53688 + 1.70 = 2.23688 g.

The moles of CF₂ are calculated as: 8.93 g / 2.23688 = 3.992, which rounds to approximately 4.

The molecular formula for CF₂ is then 4(CF₂) = C₄F₈

In alkenes, the existence of cis and trans isomers arises due to the inflexible double bond which inhibits rotation, having groups attached to the double bond's carbon atoms that remain static in relation to each other, thus leading to varying geometries; these are two distinct molecules with slightly differing characteristics. 
-Trans indicates the ends of the chain are opposite each other around the double bond.
When naming Cis-Trans isomers, the terms cis or trans are prefixed to the name of the alkene when such isomers exist.