Red cabbage contains a water-soluble pigment called anthocyanin<span> that changes color when it is mixed with an acid or a base. The pigment turns red in acidic environments with a pH less than 7 and the pigment turns bluish-green in alkaline (basic) environments with a pH greater than 7.</span>
Answer:
a) Graph
b) Weight balance or gas syringe or upside-down measuring cylinder
Explanation:
a) Identifying a trend in temperature change over time - The best tool for this scenario is to represents the temperature daily, weekly, monthly or annually on graph to interpret the fluctuation in temperature owing to local seasonal changes and weather conditions
b) Measuring the mass of a product of a chemical reaction - If the product is solid or liquid then the balance is used to measure the mass. If the product is a gas, then gas syringe or upside-down measuring cylinder is used.
<u>Answer:</u> The final temperature of water is 32.3°C
<u>Explanation:</u>
When two solutions are mixed, the amount of heat released by solution 1 (liquid water) will be equal to the amount of heat absorbed by solution 2 (liquid water)
The equation used to calculate heat released or absorbed follows:
![m_1\times c\times (T_{final}-T_1)=-[m_2\times c\times (T_{final}-T_2)]](https://tex.z-dn.net/?f=m_1%5Ctimes%20c%5Ctimes%20%28T_%7Bfinal%7D-T_1%29%3D-%5Bm_2%5Ctimes%20c%5Ctimes%20%28T_%7Bfinal%7D-T_2%29%5D)
......(1)
where,
q = heat absorbed or released
= mass of solution 1 (liquid water) = 50.0 g
= mass of solution 2 (liquid water) = 29.0 g
= final temperature = ?
= initial temperature of solution 1 = 25°C = [273 + 25] = 298 K
= initial temperature of solution 2 = 45°C = [273 + 45] = 318 K
c = specific heat of water= 4.18 J/g.K
Putting values in equation 1, we get:
![50.0\times 4.18\times (T_{final}-298)=-[29.0\times 4.18\times (T_{final}-318)]\\\\T_{final}=305.3K](https://tex.z-dn.net/?f=50.0%5Ctimes%204.18%5Ctimes%20%28T_%7Bfinal%7D-298%29%3D-%5B29.0%5Ctimes%204.18%5Ctimes%20%28T_%7Bfinal%7D-318%29%5D%5C%5C%5C%5CT_%7Bfinal%7D%3D305.3K)
Converting this into degree Celsius, we use the conversion factor:
Hence, the final temperature of water is 32.3°C
Answer:
A. Intramolecular interactions are generally stronger.
B. a. Only intermolecular interactions are broken when a liquid is converted to a gas.
Explanation:
<em>A. Which is generally stronger, intermolecular interactions or intramolecular interactions?</em>
Intramolecular interactions, in which electrons are gained, lost or shared, constitute true bonds and are one or two orders of magnitude stronger than intermolecular interactions.
<em>B. Which of these kinds of interactions are broken when a liquid is converted to a gas?</em>
When a liquid vaporizes, the intermolecular attractions are broken, that is, molecules get more separated. However, true bonds are not broken which is why the molecules keep their chemical identity.
All atoms of the same element have the same
number of protons. Every atom also has a nucleus.
