Answer:
The process of making S'more by adding chocolate bar, gram-crackers, and marshmallows in layers is not a chemical reaction
Explanation:
In a chemical reaction, the substances involved in the reaction are known as the reactants and the substances produced have different physical and chemical properties than those of the reactants and they are known as the products.
The bonds that hold the atoms of the reactants are broken down and rearranged, creating entirely new substances as products. Therefore, energy must be added and/or evolved in any chemical reaction and all reactant atoms should be involved in the reaction.
The change in energy can be sensed as heat change such as increase or decrease in the temperature of the products
Since S'more does not involve any of the above changes that occur in a chemical reaction when the chocolate bar, gram-crackers, and marshmallows are put together, it is not a chemical change or a chemical reaction.
Answer:
The total pressure is 25.7 atm
Explanation:
The total pressure is the sum of the pressures of the three gases in the flask.
total pressure=(11.4+5.6+8.7) atm
=25.7 atm
<span>a) 7.9x10^9
b) 1.5x10^9
c) 3.9x10^4
To determine what percentage of an isotope remains after a given length of time, you can use the formula
p = 2^(-x)
where
p = percentage remaining
x = number of half lives expired.
The number of half lives expired is simply
x = t/h
where
x = number of half lives expired
t = time spent
h = length of half life.
So the overall formula becomes
p = 2^(-t/h)
And since we're starting with 1.1x10^10 atoms, we can simply multiply that by the percentage. So, the answers rounding to 2 significant figures are:
a) 1.1x10^10 * 2^(-5/10.5) = 1.1x10^10 * 0.718873349 = 7.9x10^9
b) 1.1x10^10 * 2^(-30/10.5) = 1.1x10^10 * 0.138011189 = 1.5x10^9
c) 1.1x10^10 * 2^(-190/10.5) = 1.1x10^10 * 3.57101x10^-6 = 3.9x10^4</span>
A chemical change produces a new substances. Examples of chemical changes are burning a cooking egg
Answer:
3rd statment
Explanation:
ray 1 and 2 are same vertical line
