6.
7. 6 × 7 = 42
42 ÷ 10 = 4,2 Pizzas
You need to buy 4 or 5 Pizzas.
Answer:

Explanation:
Given that,
Mass of a glass, m = 4 g
Initial temperature, 
Final temperature, 
Heat absorbed, Q = 32 J
We need to find the specific heat of the glass. The formula for the heat absorbed is given by :

So, the required specific heat of the glass is
.
Number one is true !!!!!!????!???????????!!!!!!!!!!!!
The temperature at which phase changes occur is highly dependent on the electrostatic forces between the molecules in the substance.
The forces that hold molecules together are called intermolecular forces. These intermolecular forces affect the temperature at which phase changes occur. The statement about phase changes and electrostatic forces that is correct is that; "the temperatures at which a substance changes phases indicate the relative strength of the forces between molecules in the substance."
There are three states of matter, solid liquid and gas. The order of intermolecular forces in all the states of matter are not the same. The order of strongest collective electrostatic forces to weakest collective electrostatic forces is; solid, liquid, gas.
When water boils, the forces between water molecules break, and the bonds between the atoms in water are unchanged.
When a sample of calcium carbonate is cooled, the forces strengthen, and the molecule structure becomes more rigid.
If the boiling point of acetone is lower than the boiling point of ethanol, then, the intermolecular forces in ethanol are stronger than the intermolecular forces in acetone.
Learn more about phase changes: brainly.com/question/671212
Answer:
2 H₃PO₄(aq) + 3 Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + 6 H₂O(l)
Explanation:
Let's consider the unbalanced equation that occurs when phosphoric acid reacts with barium hydroxide to form water and barium phosphate. This is a neutralization reaction.
H₃PO₄(aq) + Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + H₂O(l)
We will balance it using the trial and error method.
First, we will balance Ba atoms by multiplying Ba(OH)₂ by 3 and P atoms by multiplying H₃PO₄ by 2.
2 H₃PO₄(aq) + 3 Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + H₂O(l)
Finally, we will get the balanced equation by multiplying H₂O by 6.
2 H₃PO₄(aq) + 3 Ba(OH)₂(aq) ⇒ Ba₃(PO₄)₂(s) + 6 H₂O(l)