Explanation:
A Giant Gas Cloud. A star begins life as a large cloud of gas.
A Protostar Is a Baby Star.
The T-Tauri Phase.
Main Sequence Stars.
Expansion into Red Giant.
Fusion of Heavier Elements.
Supernovae and Planetary Nebulae.
Answer:
- 40.66
- 9.91
Explanation:
For the first question:
Our theoretical compound is MR₂
1 mol of MR₂ contains 1 mol of M and 2 moles of R
Let's find out the molar mass:
9.45 g/mol + 18.12 g/mol . 2 = 45.69 g/mol
We can solve this, by an easy rule of three:
1 mol of MR₂ weighs 45.69 grams
Then, 0.89 moles may weigh 40.66 g
For the second question:
Our theoretical compound is D₂G
Let's determine the molar mass:
11.45 g/mol . 2 + 44.57 g/mol = 67.47 g/mol
1 mol of anything contains 6.02×10²³ molecules. By this definition we can say that 6.02×10²³ molecules weigh 67.47 grams. Let's solve by the rule of three:
6.02×10²³ molecules weigh 67.47 g
8.84×10²² molecules may weigh (8.84×10²² . 67.47 ) / 6.02×10²³ = 9.91 g
When the candle is lit and burn to liquid wax, it still has its originally mass, but in liquid form
Answer:
IF the fruit juice contains a high level of vitamin C, THEN the preventative effectiveness against common cold increases.
Explanation:
The hypothesis is a testable explanation of a scientific investigation. It aims at predicting the outcome of the experiment. One feature of the hypothesis is that it must be testable. The hypothesis is usually written in an "IF, THEN" format.
This question is regarding an experiment to test the amount of vitamin C in fruit juice. The vitamin C is thought to be an effective preventative against common cold. Hence, the hypothesis connects the effect on common cold (dependent variable) with the amount of vitamin C (independent variable). The hypothesis can be written as:
IF the fruit juice contains a high level of vitamin C, THEN the preventative effectiveness against common cold increases.
The objects may exchange heat between each other if they are in contact with each other.
The two objects will allow flow of heat between them if they have a difference in temperature from each other.
The heat will flow from higher temperature object to lower temperature object. The will reach a final temperature (common to each other) and then there will be no heat transfer between each other.
