**Answer:**

Now eating can change food both physically and chemically. Once your spit touches the food chemicals in the saliva begin to change the food chemically.

**Explanation:**

**Answer: The balloon will not survive.**

**Explanation:**

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

**The combined gas equation is,**

where,

= initial pressure of gas = 1 atm

= final pressure of gas = 0.05 atm

= initial volume of gas = 4.0 L

= final volume of gas = ?

= initial temperature of gas =

= final temperature of gas =

Now put all the given values in the above equation, we get:

**As the balloon has the capacity to expand to a 50 liter volume before bursting, it can not survive as it occupies volume higher than 50 L**

**Answer:**

See to them if they are balanced, i.e., the no. of atoms of each element should be equal on both the sides. If they are so, then its adhered to law of conservation of matter.

**Answer:**

- line segment of length 8 between the vertices at (-1, -2) and (-1, 6)

**Explanation:**

The equation can be rearranged to standard form.

(y^2 -4y) -4(x^2 +2x) = 16

(y^2 -4y +4) -4(x^2 +2x +1) = 16 +4 -4

(y -2)^2 -4(x +1)^2 = 16

(y -2)^2 /16 -(x +1)^2/4 = 1

This is of the form ...

(y -k)^2/a^2 -(x -h)^2/b^2 = 1

where the transverse axis is 2a and the center is (h, k). Here, a=4, so **2a = 8**.

**The transverse axis is a vertical line segment of length 8, centered on (-1, 2)**.

This problem is providing us with the **chemical** **equation **for the **decomposition **of **water **to **hydrogen** and **oxygen**, the involved **bond** **energies **and asks for the **total** **energy **of the reaction as well as whether it is **endothermic **or **exothermic**. At the end, one comes to the conclusion that it is **exothermic **because the **total energy** is** -425 kJ**.

<h3>Bond energy:</h3>

In chemistry, **bond energies **are defined as the **necessary **energy to **break **a **bond between **two **atoms**. In this case, we see that **water**, **H2O** has **two H-O bonds **and **hydrogen **and **oxygen **have two **H-H** and one **O=O** **bonds**, respectively.

Thus, we **write **the following **heat equation**, which comprises the aforementioned **bond energies **and the **stoichiometric coefficients **in the reaction:

Hence, we **plug in **the given **bond energies **to obtain:

Where the **negative **suggests this is an **exothermic reaction **as it **releases energy **(negative enthalpy).

Learn more about bond energies: brainly.com/question/26141360