Answer:
A is the answer. Chemical changes happen when atomic bonds are broken or created during chemical reactions. Hence, in this case, it involve changes to molecular structure.
- Change in states are physical changes.
- When salts are dissolved in water, you can use Distillation to separate them. Distillation is a physical change as well.
- Dissolving is just physical change.
Explanation:
The statement that is true of a chemical change among the statements given in the question is "It involves changes in the molecular structure". The correct option among all the options that are given in the question is the first option or option "A". I hope the answer has actually come to your help.
Answer:
13 minutes
Explanation:
For the endothermic reaction to reach 0°C, it will take 13 minutes.
Let us follow the process step by step;
Rate of decrease is 2°C per minute.
Start is 26°C
Time temperature
0 min 26°C
1 min 24°C
2 min 22°C
3 min 20°C
4 min 18°C
5 min 16°C
6 min 14°C
7 min 12°C
8 min 10°C
9 min 8°C
10 min 6°C
11 min 4°C
12 min 2°C
13 min 0°C
Quantitative observation have accuracy over qualitative observation as in Quantitative observation data is recorded in terms of number .
Explanation:
Qualitative observations are descriptive observations that don't involve numbers. " The freezing point of water is colder than the boiling point " is an example. Quantitative observations are numerical measurements. "The freezing point of watrr is 0 c and boiling point is 100 c" is a quantitative observation.
<span>43.83g of nacl are required to </span><span>make 500.0 ml of a 1.500 m solution.</span>
Grasslands are areas where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur naturally on all continents except Antarctica and are found in most ecoregions of the Earth. Furthermore, grasslands are one of the largest biomes on earth and dominate the landscape worldwide.[1] They cover 31-43% of the Earth's land area. There are different types of grasslands: natural grasslands, semi-natural grasslands, and agricultural grasslands.[1]