What is the specific heat of silicon if it takes 192J to raise the temperature of 45.0g of Si by 6.0oC?

A compound signifies a substance comprised of two or more elements that have undergone a chemical combination. A polyatomic ion, often referred to as a molecular ion, represents a charged particle formed from two or more atoms. An example would be the nitrate ion (NO3-), which consists of one nitrogen atom and three oxygen atoms covalently bonded, acting as a single charged entity. Thus, the apt term would be a polyatomic ion or a molecular ion.

Answer:

3.816 × 10⁻³ M

Explanation:

A stock solution of Cu²⁺(aq) is made by dissolving 0.8875 g of solid Cu(NO₃)₂∙2.5H₂O in a 100.0-mL volumetric flask, and then brought up to volume with water. What is the molarity (in M) of Cu²⁺(aq) in this stock solution?

We can derive the following relations:

• The molar mass of Cu(NO₃)₂∙2.5H₂O is 232.59 g/mol.
• Each mole of Cu(NO₃)₂∙2.5H₂O yields one mole of Cu²⁺.

The moles of Cu²⁺ present in 0.8875 g of Cu(NO₃)₂∙2.5H₂O are:

The molarity of Cu²⁺ is:

(c) Cu + S → CuS is classified as a redox reaction

Explanation:

The following reactions are presented:

(a) K₂CrO₄ + BaCl₂ → BaCrO₄ + 2 KCl

(b) Pb²⁺ + 2 Br⁻ → PbBr₂

(c) Cu + S → CuS

Reaction (c) represents a redox reaction, as the oxidation states of the elements are changing. In this case:

Cu + S → CuS

In its elemental form, Cu has an oxidation state of 0, while in CuS (copper sulfide), its oxidation state changes to +2.

Similarly, S in its elemental form has an oxidation state of 0 and is -2 in CuS (copper sulfide).

Learn more about:

redox reactions

Specific heat refers to the quantity of heat a material can absorb or release to alter its temperature by one degree Celsius. To calculate specific heat, we apply the equation for the heat absorbed by the system. The heat taken in or released by a system can be expressed by multiplying the mass of the substance by its specific heat capacity and the change in temperature. The formula is:
Heat = mC(T2-T1)
By substituting the provided values, we can find C, the specific heat of the substance.
2510 J = 0.158 kg (1000 g / 1 kg)(C)(61.0 - 32.0 °C) C = 0.5478 J/g°C

Answer: Copper is being oxidized and acts as a reducing agent. In contrast, silver is being reduced, functioning as the oxidizing agent.

Explanation:

An oxidation reaction involves the loss of electrons by an atom. Here, the oxidation state of the atom rises.

Conversely, a reduction reaction is characterized by an atom gaining electrons, resulting in a decrease in its oxidation state.

Oxidizing agents are those that facilitate the oxidation of another substance while themselves being reduced. These substances participate in reduction reactions.

Reducing agentsare defined as those that reduce other substances while undergoing oxidation themselves. They also take part in reduction reactions.

In the provided chemical reaction:

The associated half-reactions for the above process are:

Oxidation half reaction:  

Reduction half reaction:  

From the reactions outlined, copper is losing electrons. Consequently, it is oxidized and regarded as a reducing agent.

Silver is acquiring electrons, thus it is being reduced and viewed as an oxidizing agent.