Pls thx! : ) two states of matter are described below. state a: changes shape and volume state b: changes shape but not volume which combination of the state and a substance in that state is correct? state a = juice; state b = block of wood state a = hydrogen; state b = block of wood state a = oxygen; state b = juice state a = air; state b = neon

in general there are rhree states of matter

1. Solid

2. liquid

3.Gas

Solids are characterized by a fixed shape and volume. They do not change their shape and volume with container as the particles in them are closely packed and have strong intermolecular forces of attraction.

In case of liquids they have definite volume however they do acquire the shape of container. the molecules less closely placed than solid as they have weaker intermolecular forces of attraction as compared to solids.

Gas has neither definite shape not definite volume.

They have weakest force of attractions

hence answer is

State A: changes shape and volume, muat be a gas

State B: changes shape but not volume , must be a liquid

State A: oxygen gas

State B: juice

idk i’m struggling too

when 25.0 ml of 0.700 mol/l naoh was mixed in a calorimeter with 25.0 ml of 0.700 mol/l hcl, both initially at 20.0 °c, the temperature increased to 22.1 °c. the heat capacity of the calorimeter is 279 j/°c.

the equation for the reaction is:

naoh + hcl → nacl + h₂o

moles of hcl = 0.0250 l hcl ×

0.700

mol hcl

1 l hcl = 0.0175 mol hcl

volume of solution = (25.0 + 25.0) ml = 50.0 ml

mass of solution = 50.0 ml soln ×

1.00

ml soln

= 50.0 g soln

δt=t2-t1

= (22.1 – 20.0) °c = 2.1 °c

the heats involved are

heat from neutralization + heat to warm solution + heat to warm calorimeter = 0

q1+q2+q3=0

nδh+mcδt+cδt=0

0.0175 mol ×

δh

+ 50.0 g × 4.184 j·g⁻¹°c⁻¹ × 2.1 °c + 279 j°c⁻¹ × 2.1 °c = 0

0.0175 mol ×

δh

+ 439.32 j + 585.9 j = 0

0.0175 mol ×

δh

= -1025.22 j

δh=1025.22j0.0175 mol= -58 600 j/mol = -58.6 kj/mol