Answer:
1: Elements are substances that cannot be broken down into more substances.
2: Compounds are a group of elements in a specific ratio.
3: A metalloid is between a metal and a non-metal.
4: A physical property is a property you can see or touch.
5: A chemical property is a property seen in chemical reactions.
6: Alloys are the combination of two or more metals to make a better material.
7: An insulator doesn't let heat and sound escape.
8: Corrosion is when a metal reacts to oxygen, water, or sulfur.
9: Rust is when a metal is exposed to oxygen
Explanation:
Answer:
D. Validity group
Explanation:
A validity group is not necessarily a component of a normal experiment.
A normal experiment is made up of the dependent variables, independent variables, and most times the control group.
- The dependent variable is one that relies on the outcome of the effect produced from the experimental design
- The independent variable is the one that causes a desired effect under the study.
- The control group is a group that does not receive any treatment nor attenuation of the conditions.
Answer:
r = 0.5 m
Explanation:
First we find the angular speed of the ball by using its period:
ω = θ/t
For the time period:
ω = angular speed = ?
θ = angular displacement = 2π rad
t = time period = 0.5 s
Therefore,
ω = 2π rad/0.5 s
ω = 12.56 rad/s
Now, for the radius:
v = rω
r = v/ω
where,
v = linear speed = 6.29 m/s
r = radius = ?
r = (6.29 m/s)/(12.56 rad/s)
<u>r = 0.5 m</u>
Answer: ![-\frac{1}{2}\times \frac{d[Br^.]}{dt}=+\frac{d[Br_2]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1%7D%7B2%7D%5Ctimes%20%5Cfrac%7Bd%5BBr%5E.%5D%7D%7Bdt%7D%3D%2B%5Cfrac%7Bd%5BBr_2%5D%7D%7Bdt%7D)
Explanation:
Rate of a reaction is defined as the rate of change of concentration per unit time.
Thus for reaction:

The rate in terms of reactants is given as negative as the concentration of reactants is decreasing with time whereas the rate in terms of products is given as positive as the concentration of products is increasing with time.
![Rate=-\frac{d[Br^.]}{2dt}](https://tex.z-dn.net/?f=Rate%3D-%5Cfrac%7Bd%5BBr%5E.%5D%7D%7B2dt%7D)
or ![Rate=+\frac{d[Br_2]}{dt}](https://tex.z-dn.net/?f=Rate%3D%2B%5Cfrac%7Bd%5BBr_2%5D%7D%7Bdt%7D)
Thus ![-\frac{d[Br^.]}{2dt}=+\frac{d[Br_2]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7Bd%5BBr%5E.%5D%7D%7B2dt%7D%3D%2B%5Cfrac%7Bd%5BBr_2%5D%7D%7Bdt%7D)